{"id":1603,"date":"2022-07-10T11:11:12","date_gmt":"2024-07-10T11:22:12","guid":{"rendered":"http:\/\/ialert.com\/blog\/?p=1603"},"modified":"2026-04-28T02:07:37","modified_gmt":"2026-04-28T02:07:37","slug":"glossary-of-weather-terms-beginning-with-s","status":"publish","type":"post","link":"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/glossary-of-weather-terms-beginning-with-s\/","title":{"rendered":"Glossary of Weather Terms &#8211; Beginning with &#8220;S&#8221;"},"content":{"rendered":"<p>Looking up the <strong>Saffir-Simpson hurricane scale<\/strong>, the difference between a <strong>severe thunderstorm warning vs tornado warning<\/strong>, <strong>what a supercell is<\/strong>, or what a <strong>storm surge warning<\/strong> or <strong>snow squall warning<\/strong> means for your safety?<\/p>\n<h3>Jump to weather terms beginning with the letter:<\/h3>\n<p style=\"text-align: center;\"><a title=\"Weather Terms Beginning With &quot;A&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-a\/\" rel=\"nofollow\">A<\/a> | <a title=\"Weather Terms Beginning With &quot;B&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-b\/\" rel=\"nofollow\">B<\/a> | <a title=\"Weather Terms Beginning With &quot;C&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-c\/\" rel=\"nofollow\">C<\/a> | <a title=\"Weather Terms Beginning with &quot;D&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-d\/\" rel=\"nofollow\">D<\/a> | <a title=\"Weather Terms Beginning With &quot;E&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-e\" rel=\"nofollow\">E<\/a> | <a title=\"Weather Terms Beginning with &quot;F&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-f\/\" rel=\"nofollow\">F<\/a> | <a title=\"Weather Terms Beginning With &quot;G&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-g\/\" rel=\"nofollow\">G<\/a> | <a title=\"Weather Terms Beginning with &quot;H&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-h\/\" rel=\"nofollow\">H<\/a> | <a title=\"Weather Terms Beginning with &quot;I&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-i\/\" rel=\"nofollow\">I<\/a> | <a title=\"Weather Terms Beginning With &quot;J&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-j\/\" rel=\"nofollow\">J<\/a> | <a title=\"Weather Terms Beginning With &quot;K&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-k\/\" rel=\"nofollow\">K<\/a> | <a title=\"Weather Terms Beginning with &quot;L&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-l\/\" rel=\"nofollow\">L<\/a> | <a title=\"Weather Terms Beginning with &quot;M&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-M\/\" rel=\"nofollow\">M<\/a> | <a title=\"Weather Terms Beginning with &quot;N&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-n\/\" rel=\"nofollow\">N<\/a> | <a title=\"Weather Terms Beginning With &quot;O&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-o\/\" rel=\"nofollow\">O<\/a> | <a title=\"Weather Terms Beginning With &quot;P&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-p\/\" rel=\"nofollow\">P<\/a> | <a title=\"Weather Terms Beginning With &quot;Q&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-q\/\" rel=\"nofollow\">Q<\/a> | <a title=\"Weather Terms Beginning With &quot;R&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-r\" rel=\"nofollow\">R<\/a> | <a title=\"Weather Terms Beginning with &quot;S&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-s\/\" rel=\"nofollow\">S<\/a> | <a title=\"Weather Terms Beginning With &quot;T&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-t\/\" rel=\"nofollow\">T<\/a> | <a title=\"Weather Terms Beginning With &quot;U&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-u\/\" rel=\"nofollow\">U<\/a> | <a title=\"Weather Terms Beginning With &quot;V&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-v\/\" rel=\"nofollow\">V<\/a> | <a title=\"Weather Terms Beginning With &quot;W&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-w\/\" rel=\"nofollow\">W<\/a> | <a title=\"Weather Terms Beginning With &quot;X&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-x\/\" rel=\"nofollow\">X<\/a> | <a title=\"Weather Terms Beginning With &quot;Y&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-y\/\" rel=\"nofollow\">Y<\/a> | <a title=\"Weather Terms Beginning With &quot;Z&quot;\" href=\"http:\/\/ialert.com\/blog\/weather-glossary\/glossary-of-weather-terms-beginning-with-z\/\" rel=\"nofollow\">Z<\/a><\/p>\n<div style=\"background: #1a3a5c; padding: 20px 24px; margin: 20px 0; border-radius: 4px;\">\n<p style=\"color: #ffffff; font-size: 16px; font-weight: bold; margin: 0 0 6px 0;\">Get Severe Weather Alerts for Your Location<\/p>\n<p style=\"color: rgba(255,255,255,0.9); margin: 0 0 14px 0;\">When any NWS watch, warning, or advisory is issued for your area, iAlert sends you an immediate notification by email or text, 24 hours a day, 7 days a week.<\/p>\n<p><a href=\"https:\/\/iAlert.com\/services\/product-details.php?pro-id=15\" style=\"background: #C41226; color: #ffffff; padding: 10px 22px; text-decoration: none; border-radius: 3px; font-weight: bold; display: inline-block;\" target=\"_blank\" rel=\"noopener\">Sign Up for Severe Weather Alerts &rarr;<\/a>\n<\/div>\n<hr \/>\n<h3><strong>Weather Terms Beginning with &#8220;S&#8221;<\/strong><\/h3>\n<h4 style=\"margin-top: 24px;\" id=\"saffir-simpson\"><strong>Saffir-Simpson Hurricane Wind Scale<\/strong><\/h4>\n<p>The Saffir-Simpson Hurricane Wind Scale is the 1-5 scale used to rate the intensity of Atlantic and eastern Pacific tropical cyclones based solely on sustained wind speed. It was introduced by structural engineer Herbert Saffir and National Hurricane Center director Robert Simpson in 1971. The scale correlates wind speed ranges with estimated property damage levels:<\/p>\n<ul>\n<li><strong>Category 1 (74-95 mph):<\/strong> Some roof damage and broken branches; power outages lasting days to a week<\/li>\n<li><strong>Category 2 (96-110 mph):<\/strong> Extensive roof and siding damage, trees uprooted; power outages lasting weeks<\/li>\n<li><strong>Category 3, Major (111-129 mph):<\/strong> Devastating damage to well-built homes; most structures damaged; power outages lasting weeks to months<\/li>\n<li><strong>Category 4, Major (130-156 mph):<\/strong> Catastrophic damage; most exterior walls fail; long-term power and water outages<\/li>\n<li><strong>Category 5, Major (157+ mph):<\/strong> Total destruction of most residential and commercial buildings; complete power and water loss for months<\/li>\n<\/ul>\n<p>An important limitation: storm surge is NOT included in the Saffir-Simpson scale. A Category 2 storm making landfall in a shallow bay with an unfavorable angle can produce Category 4-level storm surge. Always follow Storm Surge Watch and Warning products from the National Hurricane Center independently of the storm category.<\/p>\n<p>See also: <a title=\"Saffir-Simpson Hurricane Wind Scale\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/saffir-simpson-hurricane-wind-scale\/\">Saffir-Simpson Hurricane Wind Scale explained<\/a> | <a title=\"Criteria for a Hurricane Warning\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/criteria-for-a-hurricane-warning\/\">Criteria for a Hurricane Warning<\/a><\/p>\n<h4 style=\"margin-top: 24px;\"><strong>Saffir-Simpson Hurricane Wind Scale<\/strong><\/h4>\n<table style=\"width:100%; border-collapse:collapse; margin:16px 0; font-size:14px;\">\n<thead>\n<tr style=\"background:#1a3a5c; color:#ffffff;\">\n<th style=\"padding:10px 12px; text-align:left;\">Category<\/th>\n<th style=\"padding:10px 12px; text-align:left;\">Sustained Winds<\/th>\n<th style=\"padding:10px 12px; text-align:left;\">Surge Potential<\/th>\n<th style=\"padding:10px 12px; text-align:left;\">Damage Level<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background:#ffffff; border-bottom:1px solid #e0e0e0;\">\n<td style=\"padding:9px 12px; font-weight:bold;\">1<\/td>\n<td style=\"padding:9px 12px;\">74-95 mph<\/td>\n<td style=\"padding:9px 12px;\">4-5 ft<\/td>\n<td style=\"padding:9px 12px;\">Minimal, very dangerous winds<\/td>\n<\/tr>\n<tr style=\"background:#f9f9f9; border-bottom:1px solid #e0e0e0;\">\n<td style=\"padding:9px 12px; font-weight:bold;\">2<\/td>\n<td style=\"padding:9px 12px;\">96-110 mph<\/td>\n<td style=\"padding:9px 12px;\">6-8 ft<\/td>\n<td style=\"padding:9px 12px;\">Extensive, extremely dangerous winds<\/td>\n<\/tr>\n<tr style=\"background:#fff3f3; border-bottom:1px solid #e0e0e0;\">\n<td style=\"padding:9px 12px; font-weight:bold; color:#C41226;\">3, MAJOR<\/td>\n<td style=\"padding:9px 12px;\">111-129 mph<\/td>\n<td style=\"padding:9px 12px;\">9-12 ft<\/td>\n<td style=\"padding:9px 12px;\">Devastating, major hurricane<\/td>\n<\/tr>\n<tr style=\"background:#fff3f3; border-bottom:1px solid #e0e0e0;\">\n<td style=\"padding:9px 12px; font-weight:bold; color:#C41226;\">4, MAJOR<\/td>\n<td style=\"padding:9px 12px;\">130-156 mph<\/td>\n<td style=\"padding:9px 12px;\">13-18 ft<\/td>\n<td style=\"padding:9px 12px;\">Catastrophic, major hurricane<\/td>\n<\/tr>\n<tr style=\"background:#fff3f3; border-bottom:1px solid #e0e0e0;\">\n<td style=\"padding:9px 12px; font-weight:bold; color:#C41226;\">5, MAJOR<\/td>\n<td style=\"padding:9px 12px;\">157+ mph<\/td>\n<td style=\"padding:9px 12px;\">19+ ft<\/td>\n<td style=\"padding:9px 12px;\">Complete destruction, major hurricane<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h4 style=\"margin-top: 24px;\" id=\"severe-thunderstorm-watch\"><strong>Severe Thunderstorm Watch<\/strong><\/h4>\n<p>A Severe Thunderstorm Watch is issued by the Storm Prediction Center (SPC) in Norman, Oklahoma when atmospheric conditions are favorable for severe thunderstorms, defined as producing hail 1 inch or larger and\/or wind gusts of 58 mph or higher, across a large multi-county area over the next 4-8 hours. A Watch covers a broad geographic area and tells people to be alert, monitor weather media, and be ready to seek shelter quickly. It does not mean severe weather is occurring, it means the atmosphere is loaded and severe storms are possible. Watches are distinct from Warnings: a Severe Thunderstorm Warning is issued by local NWS offices when a specific, individual storm is already producing or is about to produce severe criteria.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"severe-thunderstorm-warning\"><strong>Severe Thunderstorm Warning<\/strong><\/h4>\n<p>A Severe Thunderstorm Warning is issued by the local NWS office when a specific thunderstorm is occurring or is imminent and meets severe criteria: hail 1 inch (quarter size) or larger in diameter, and\/or wind gusts of 58 mph or higher. When a Severe Thunderstorm Warning is issued, take shelter immediately in a sturdy building away from windows. The NWS has enhanced the SVR Warning system with threat tags that communicate severity within the warning: a &#8220;Considerable&#8221; SVR tag is applied when hail is 1.75 inches (golf ball) or larger, or winds reach 70 mph or higher; a &#8220;Destructive&#8221; SVR tag, the highest level, is applied when hail is 2.75 inches (baseball) or larger, or winds reach 80 mph or higher. Destructive-tagged severe thunderstorm warnings should be treated with near-tornado urgency, baseball-size hail can shatter car windshields and inflict serious injury on unprotected people outdoors, and 80 mph winds can destroy poorly constructed buildings and overturn mobile homes.<\/p>\n<p>See also: <a title=\"Criteria for a Severe Thunderstorm Warning\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/criteria-for-a-severe-thunderstorm-warning\/\">Criteria for a Severe Thunderstorm Warning<\/a><\/p>\n<h4 style=\"margin-top: 24px;\" id=\"snow-squall-warning\"><strong>Snow Squall Warning<\/strong><\/h4>\n<p>A Snow Squall Warning is issued by the NWS when an intense, brief, but dangerous band of heavy snow combined with strong winds, usually 30 mph or higher, is expected to cause near-zero visibility and rapid accumulation and icing on road surfaces. Unlike a Winter Storm Warning, which covers extended snowfall periods over many hours, a Snow Squall Warning targets a specific, fast-moving band of dangerous conditions along the squall line&#8217;s path, often with only 30-60 minutes of advance notice. Highway pile-up crashes have killed dozens of people when unexpected snow squalls descended on interstate highways, instantly reducing visibility to zero and coating road surfaces with ice. The NWS introduced a dedicated Snow Squall Warning product in 2018 specifically to address these life-threatening traffic situations. Treat a Snow Squall Warning like a tornado warning on the highway, if possible, safely exit the road, pull into a parking lot, and wait for the squall to pass. If you cannot exit, slow down, turn on hazard lights, and increase following distance dramatically.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"special-weather-statement\"><strong>Special Weather Statement (SWS)<\/strong><\/h4>\n<p>A Special Weather Statement is an NWS product that provides information about weather conditions that are significant to public safety but do not meet the criteria for a formal Watch, Warning, or Advisory. An SWS is used to highlight developing severe weather before it reaches warning criteria, brief localized flooding of small streams, patchy frost, dense fog forming in specific locations, or general public safety hazards related to weather. It also serves to describe notable recent weather events, including confirming a tornado touchdown or a significant hail report. The Special Weather Statement operates informally below the Advisory level and is often issued when thunderstorms are developing and are expected to reach warning criteria within 30-60 minutes, giving the public an early heads-up.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"squall-line\"><strong>Squall Line<\/strong><\/h4>\n<p>A squall line is a long, organized line of thunderstorms that can stretch 100 to over 1,000 miles, typically associated with a cold front or an outflow boundary from previous convection. Unlike isolated supercells, a squall line produces hazards across its entire length simultaneously, widespread damaging winds, heavy rainfall, and sometimes embedded tornadoes along hundreds of miles of territory at once. Squall lines are most dangerous in the hours before and after sunset, when the atmosphere is often still unstable from daytime heating but darkness reduces visibility and public awareness. Some squall lines develop a bow-echo shape on radar, a bowing segment that indicates a concentrated zone of damaging straight-line winds that can exceed 80-100 mph. Squall lines typically move at 30-60 mph and can pass through a city with only 15-30 minutes of lead time from the time storms first become visible on radar to a citizen&#8217;s location.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"storm-prediction-center\"><strong>Storm Prediction Center (SPC)<\/strong><\/h4>\n<p>The Storm Prediction Center is the national NWS center located in Norman, Oklahoma that monitors severe convective weather and fire weather potential across the continental United States and adjacent offshore waters. The SPC operates 24 hours a day, 365 days a year, and is part of NOAA&#8217;s National Centers for Environmental Prediction (NCEP). Its primary products include the Convective Outlook (issued for Days 1 through 8), which categorizes severe weather risk into five levels, Marginal, Slight, Enhanced, Moderate, and High; Severe Thunderstorm Watches and Tornado Watches covering large multi-county areas; Mesoscale Discussions that analyze developing severe weather situations in real time; and Fire Weather Outlooks. The SPC&#8217;s Day 1 High Risk, the highest category, is issued only approximately 3-4 times per decade. It signifies the potential for a major, historic severe weather outbreak with widespread significant and violent tornadoes, destructive wind events, or both. When a High Risk is issued, emergency managers and the public in the affected area should treat it with maximum seriousness.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"storm-surge\"><strong>Storm Surge<\/strong><\/h4>\n<p>Storm surge is the abnormal rise of water above the predicted astronomical tide level produced by the wind stress and low atmospheric pressure of an approaching and landfalling tropical cyclone. It is the most deadly and destructive single element of a hurricane, the majority of hurricane fatalities historically have been caused by storm surge drowning, not wind. The surge is driven primarily by the onshore winds piling ocean water against the coast; a shallowly sloping ocean bottom amplifies the surge by preventing water from spreading laterally. Hurricane Katrina&#8217;s storm surge reached 25-28 feet in parts of coastal Mississippi in 2005, obliterating entire communities miles from the beach. Surge can extend miles inland along low-lying coastlines, bays, and tidal rivers. The National Hurricane Center began issuing dedicated Storm Surge Watches and Warnings in 2017 specifically because the Saffir-Simpson scale does not capture surge risk, a compact, fast-moving Category 4 storm can produce less surge than a large, slow-moving Category 2.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"storm-surge-warning\"><strong>Storm Surge Warning<\/strong><\/h4>\n<p>A Storm Surge Warning is issued by the National Hurricane Center when there is a danger of life-threatening inundation from rising water moving inland from the shoreline, generally within 36 hours of the onset of surge conditions. Surge height ranges are specified for individual coastal zones. A Storm Surge Watch is issued 48 hours in advance when conditions are possible. When a Storm Surge Warning is issued for your area, follow evacuation orders from local authorities without delay. The NHC consistently emphasizes that storm surge is the primary reason coastal residents are ordered to evacuate before a hurricane, you cannot wait until the wind arrives to leave a surge zone, because roads may already be flooded. Six feet of storm surge can sweep away a vehicle; 9 feet can destroy a single-story home; 20-plus feet of surge as occurred in Katrina leaves nothing standing. Evacuation is the only survivable response.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"supercell\"><strong>Supercell<\/strong><\/h4>\n<p>A supercell is the most organized, intense, and long-lived type of thunderstorm, defined by the presence of a persistent, deep, rotating updraft called a mesocyclone. Supercells produce the vast majority of violent tornadoes, those rated EF2 and stronger, as well as extremely large hail (2 inches or greater), widespread damaging winds, and dangerous lightning. They are classified into three broad types: classic supercells (the most common, with the distinctive &#8220;LP-supercell&#8221; low-precipitation and &#8220;HP-supercell&#8221; high-precipitation variants), each with different risk profiles. A classic supercell can persist for 4-12 hours and travel 100-500+ miles, in some cases crossing multiple states. The classic supercell&#8217;s distinctive visual features include a wall cloud (a localized lowering of the cloud base indicating intense rotation), a flanking line of towering cumulus, a rear-flank downdraft clear slot, and a striated rotating updraft tower. On Doppler radar, supercells are identified by their hook echo, strong velocity couplet (rotation signature), and persistent, organized reflectivity core. British meteorologist Keith Browning first described the supercell structure in detail in 1962.<\/p>\n<p>See also: <a title=\"What is a Supercell?\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/what-is-a-supercell\/\">What is a Supercell thunderstorm?<\/a> | <a title=\"How tornadoes form\" href=\"https:\/\/ialert.com\/blog\/basic-meteorology\/how-tornadoes-form\/\">How tornadoes form<\/a><\/p>\n<h4 style=\"margin-top: 24px;\" id=\"sleet\"><strong>Sleet (Ice Pellets)<\/strong><\/h4>\n<p>Sleet consists of solid precipitation in the form of transparent or translucent pellets of ice 5 millimeters or less in diameter. Sleet forms when raindrops or partially melted snowflakes fall through a shallow layer of subfreezing air, typically 1,000 to 3,000 feet deep, near the surface and completely refreeze before hitting the ground. This distinguishes sleet from freezing rain, which falls as liquid water and freezes on contact with cold surfaces. Sleet makes a distinctive tinkling or clicking sound on impact with hard surfaces. It can accumulate like snow on roadways and walkways, creating treacherous conditions; it tends to be slightly less hazardous than freezing rain because its surface coating is more granular and less uniformly glass-smooth, though it remains a serious road hazard. NWS public forecasts use the term &#8220;sleet&#8221; while the official meteorological designation is &#8220;ice pellets.&#8221;<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"storm-spotter\"><strong>Storm Spotter (Skywarn)<\/strong><\/h4>\n<p>A storm spotter is a trained volunteer who observes and reports severe weather conditions to the National Weather Service in real time during active weather events. The NWS Skywarn program, established in the 1970s, has trained over 350,000 storm spotters nationwide, making it one of the largest volunteer programs in the country. Storm spotters provide critical ground truth that cannot be obtained from radar or satellite imagery alone: they confirm tornado touchdowns and describe tornado characteristics, measure hail sizes with rulers, observe and report flooding water levels, describe wind damage, and verify conditions that help meteorologists calibrate their radar interpretation and warning decisions. Spotter reports directly influence NWS warning products and storm verification. Skywarn training is provided free of charge and offered annually through local NWS forecast offices. Amateur (ham) radio operators play an especially critical role in Skywarn communications because they can operate independently of commercial phone infrastructure during major disasters.<\/p>\n<h4 style=\"margin-top: 24px;\" id=\"saffir-simpson-surge\"><strong>Surge vs Wind: Why Category Is Not Everything<\/strong><\/h4>\n<p>The Saffir-Simpson Hurricane Wind Scale rates only one thing: sustained wind speed at landfall. It does not measure or predict storm surge, total rainfall, storm physical size, or forward speed, all of which profoundly influence a storm&#8217;s actual destructive impact. Hurricane Harvey (2017) made landfall as a Category 4 but was a Category 1 when it stalled over Houston, ultimately dropping over 60 inches of rain, the highest rainfall total ever recorded from a tropical cyclone in the US. Hurricane Michael (2018) struck as a near-Category 5 and produced catastrophic wind and surge damage but moved through quickly, limiting total rainfall. A large, slow-moving Category 2 hurricane can generate greater storm surge in a shallow bay than a compact, fast-moving Category 4 striking a steeply shelving coastline. The National Hurricane Center issues separate Storm Surge Watch and Warning products, independent of the Saffir-Simpson category, precisely because wind category alone does not communicate surge risk. When forecasters and emergency managers say &#8220;don&#8217;t focus on the category, focus on the threats,&#8221; this is exactly what they mean.<\/p>\n<hr \/>\n<div style=\"background: #1a3a5c; padding: 20px 24px; margin: 20px 0; border-radius: 4px;\">\n<p style=\"color: #ffffff; font-size: 16px; font-weight: bold; margin: 0 0 6px 0;\">Severe Weather Alerts, Any Location, Any Time<\/p>\n<p style=\"color: rgba(255,255,255,0.9); margin: 0 0 14px 0;\">From an Advisory to a Warning, iAlert monitors every NWS alert and notifies you the moment one is issued for your area. Set up alerts for home, work, school, or anywhere your family is.<\/p>\n<p><a href=\"https:\/\/iAlert.com\/services\/product-details.php?pro-id=15\" style=\"background: #C41226; color: #ffffff; padding: 10px 22px; text-decoration: none; border-radius: 3px; font-weight: bold; display: inline-block;\" target=\"_blank\" rel=\"noopener\">Get Weather Alerts &rarr;<\/a>\n<\/div>\n<hr \/>\n<h3><strong>Frequently Asked Questions, &#8220;S&#8221; Weather Terms<\/strong><\/h3>\n<h4 style=\"margin-top: 24px;\">What is the Saffir-Simpson Hurricane Wind Scale?<\/h4>\n<p>The Saffir-Simpson Hurricane Wind Scale rates tropical cyclone intensity from Category 1 (74-95 mph winds) through Category 5 (157+ mph). Categories 3, 4, and 5 are classified as &#8220;major hurricanes&#8221; capable of catastrophic damage. However, the scale only rates sustained wind speed, it does NOT measure storm surge, rainfall, or storm size. A weak Category 1 or 2 storm moving slowly can drop more rain and produce more flooding than a fast-moving Category 4. The NHC issues separate Storm Surge Watch and Warning products specifically to communicate surge hazards that the Saffir-Simpson scale does not capture.<\/p>\n<h4 style=\"margin-top: 24px;\">What is the difference between a Severe Thunderstorm Watch and Warning?<\/h4>\n<p>A Severe Thunderstorm Watch is issued by the Storm Prediction Center when conditions are favorable for severe thunderstorms across a large multi-county area in the next 4-8 hours. It means conditions are right for severe weather to develop, be alert and be ready. A Severe Thunderstorm Warning is issued by your local NWS office when a specific storm is producing or is about to produce severe criteria, hail 1 inch or larger (quarter-size) and\/or winds of 58 mph or higher. When a Warning is issued, take shelter immediately. The highest-tier &#8220;Destructive&#8221; SVR tag is used for hail of baseball size (2.75 inches) or winds of 80 mph or higher.<\/p>\n<h4 style=\"margin-top: 24px;\">What is a supercell thunderstorm?<\/h4>\n<p>A supercell is the most organized and dangerous type of thunderstorm, a long-lived storm with a persistent rotating updraft called a mesocyclone. Supercells produce the vast majority of violent (EF2+) tornadoes, extremely large hail (golf ball size or bigger), and widespread damaging winds. Unlike ordinary thunderstorms that last 30-60 minutes, supercells can persist for 4-12 hours and travel hundreds of miles. They are steered independently of other storms and can be detected on Doppler radar by their distinctive hook echo, strong rotation signature, and persistent reflectivity core. Storm chasers specifically target supercells.<\/p>\n<h4 style=\"margin-top: 24px;\">What is storm surge and why is it so dangerous?<\/h4>\n<p>Storm surge is the abnormal rise of sea water above the predicted tide level, pushed inland by the winds and low pressure of a tropical cyclone. It is the most deadly aspect of a hurricane, responsible for the majority of hurricane fatalities. Hurricane Katrina produced a storm surge of 25-28 feet in parts of Mississippi, wiping entire communities off the map. Storm surge can extend miles inland along low-lying coastlines. The NHC now issues Storm Surge Watches and Warnings that specify expected surge heights for coastal zones. Evacuate if ordered by local authorities, 6 feet of surge can sweep away a car.<\/p>\n<h4 style=\"margin-top: 24px;\">What is a Snow Squall Warning?<\/h4>\n<p>A Snow Squall Warning is issued when an intense, fast-moving band of heavy snow and strong winds (30+ mph) is expected to bring near-zero visibility and rapid road icing for a brief period, usually 30-60 minutes. Unlike Winter Storm Warnings that cover extended periods of snowfall, snow squall warnings are hyper-targeted in time and space. Highway pile-up crashes have killed and injured dozens of people when unexpected snow squalls struck interstate highways. The NWS introduced Snow Squall Warnings in 2018 specifically to save lives on highways. Treat them like a tornado warning, get off the highway immediately if possible.<\/p>\n<h4 style=\"margin-top: 24px;\">What does the Storm Prediction Center do?<\/h4>\n<p>The Storm Prediction Center (SPC) in Norman, Oklahoma monitors severe weather potential across the entire continental US and issues products that help local NWS offices, emergency managers, and the public prepare. Its products include the daily Convective Outlook (Day 1-8) categorizing severe weather risk from Marginal through High; Tornado Watches and Severe Thunderstorm Watches covering large multi-county areas; Mesoscale Discussions analyzing developing severe weather situations; and Fire Weather Outlooks. The SPC&#8217;s highest-category Day 1 High Risk is issued only 3-4 times per decade and signifies the potential for a major, historic severe weather outbreak.<\/p>\n<hr \/>\n<div style=\"background: #C41226; padding: 20px 24px; margin: 20px 0; border-radius: 4px;\">\n<p style=\"color: #ffffff; font-size: 17px; font-weight: bold; margin: 0 0 6px 0;\">Never Miss a Severe Weather Alert<\/p>\n<p style=\"color: rgba(255,255,255,0.92); margin: 0 0 14px 0;\">iAlert monitors National Weather Service watches, warnings, and advisories around the clock and sends you an immediate notification the moment your area is threatened. Works for any U.S. location.<\/p>\n<p><a href=\"https:\/\/iAlert.com\/services\" style=\"background: #ffffff; color: #C41226; padding: 10px 22px; text-decoration: none; border-radius: 3px; font-weight: bold; display: inline-block;\" target=\"_blank\" rel=\"noopener\">View All Alert Services &rarr;<\/a>&nbsp;&nbsp;<a href=\"https:\/\/iAlert.com\/services\/product-details.php?pro-id=15\" style=\"background: transparent; color: #ffffff; padding: 10px 22px; text-decoration: none; border-radius: 3px; font-weight: bold; display: inline-block; border: 2px solid rgba(255,255,255,0.8);\" target=\"_blank\" rel=\"noopener\">Severe Weather Alerts &rarr;<\/a>\n<\/div>\n<hr \/>\n<h3><strong>Related Articles<\/strong><\/h3>\n<ul>\n<li><a href=\"https:\/\/ialert.com\/services\/product-details.php?pro-id=15\">Get real-time Severe Weather Email &amp; Text Alerts<\/a><\/li>\n<li><a title=\"What is a Supercell?\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/what-is-a-supercell\/\">What is a Supercell thunderstorm?<\/a><\/li>\n<li><a title=\"Saffir-Simpson Hurricane Wind Scale\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/saffir-simpson-hurricane-wind-scale\/\">Saffir-Simpson Hurricane Wind Scale explained<\/a><\/li>\n<li><a title=\"Criteria for a Severe Thunderstorm Warning\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/criteria-for-a-severe-thunderstorm-warning\/\">Criteria for a Severe Thunderstorm Warning<\/a><\/li>\n<li><a title=\"Criteria for a Tropical Storm Warning\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/criteria-for-a-tropical-storm-warning\/\">Criteria for a Tropical Storm Warning<\/a><\/li>\n<li><a title=\"Criteria for a Hurricane Warning\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/criteria-for-a-hurricane-warning\/\">Criteria for a Hurricane Warning<\/a><\/li>\n<li><a title=\"Know the Hurricane Hazard Terms\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/know-the-hurricane-hazard-terms\/\">Know the Hurricane Hazard Terms (NHC)<\/a><\/li>\n<li><a title=\"The life cycle of a thunderstorm\" href=\"https:\/\/ialert.com\/blog\/basic-meteorology\/the-life-cycle-of-thunderstorms\">Life cycle of a thunderstorm<\/a><\/li>\n<li><a title=\"Thunderstorm basics\" href=\"https:\/\/ialert.com\/blog\/basic-meteorology\/thunderstorm-basics-structure-types-and-forecasting-methods\/\">Thunderstorm basics: structure, types, and forecasting<\/a><\/li>\n<li><a title=\"Winter Storms Preparedness\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/winter-storms-a-preparedness-guide\/\">Winter Storms, A Preparedness Guide<\/a><\/li>\n<li><a title=\"Tornado Safety\" href=\"https:\/\/ialert.com\/blog\/weather-articles\/tornado-safety\/\">Tornado Safety<\/a><\/li>\n<li><a href=\"https:\/\/ialert.com\/blog\/weather-articles\/understanding-national-weather-service-severe-weather-outlooks\/\">Understanding the NWS Severe Weather Outlook<\/a><\/li>\n<li><a href=\"https:\/\/wxdata.com\/\" target=\"_blank\" rel=\"noopener\">WxData.com, Weather Data API for apps and systems<\/a><\/li>\n<\/ul>\n<p><!-- ============================================================\n  FAQ SCHEMA, DO NOT PASTE THIS BLOCK INTO THE WP POST EDITOR\n  Add via: Rank Math > Schema tab > Custom Schema (JSON-LD)\n  ============================================================ --><br \/>\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the Saffir-Simpson Hurricane Wind Scale?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The Saffir-Simpson Hurricane Wind Scale rates tropical cyclone intensity from Category 1 (74-95 mph winds) through Category 5 (157+ mph). Categories 3, 4, and 5 are major hurricanes capable of catastrophic damage. The scale only rates sustained wind speed, it does NOT measure storm surge, rainfall, or storm size. The NHC issues separate Storm Surge Watch and Warning products specifically to communicate surge hazards that the scale does not capture.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is the difference between a Severe Thunderstorm Watch and Warning?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"A Severe Thunderstorm Watch is issued by the Storm Prediction Center when conditions are favorable for severe thunderstorms across a large multi-county area in the next 4-8 hours, be alert and be ready. A Severe Thunderstorm Warning is issued by your local NWS office when a specific storm is producing or is about to produce severe criteria: hail 1 inch or larger and\/or winds of 58 mph or higher. When a Warning is issued, take shelter immediately. The highest-tier Destructive SVR tag applies for baseball-size hail (2.75 inches) or winds of 80 mph or higher.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is a supercell thunderstorm?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"A supercell is the most organized and dangerous type of thunderstorm, a long-lived storm with a persistent rotating updraft called a mesocyclone. Supercells produce the vast majority of violent EF2+ tornadoes, extremely large hail, and widespread damaging winds. Unlike ordinary thunderstorms that last 30-60 minutes, supercells can persist for 4-12 hours and travel hundreds of miles. They are detected on Doppler radar by their distinctive hook echo and strong rotation signature.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is storm surge and why is it so dangerous?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Storm surge is the abnormal rise of sea water above the predicted tide level pushed inland by the winds and low pressure of a tropical cyclone. It is the most deadly aspect of a hurricane and responsible for the majority of hurricane fatalities. Hurricane Katrina produced 25-28 feet of storm surge in parts of Mississippi. The NHC issues Storm Surge Watches and Warnings specifying expected surge heights for coastal zones. Evacuate if ordered, 6 feet of surge can sweep away a car.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is a Snow Squall Warning?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"A Snow Squall Warning is issued when an intense, fast-moving band of heavy snow and strong winds of 30 mph or more is expected to bring near-zero visibility and rapid road icing for a brief period, usually 30-60 minutes. Unlike Winter Storm Warnings that cover extended snowfall, snow squall warnings are targeted to a specific squall line path with as little as 30 minutes of lead time. The NWS introduced Snow Squall Warnings in 2018 specifically to prevent highway pile-up crashes. Treat a Snow Squall Warning like a tornado warning and get off the highway immediately if possible.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What does the Storm Prediction Center do?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The Storm Prediction Center in Norman, Oklahoma monitors severe weather potential across the continental US and issues the daily Convective Outlook (Day 1-8) categorizing severe weather risk from Marginal through High; Tornado and Severe Thunderstorm Watches; Mesoscale Discussions; and Fire Weather Outlooks. The SPC operates 24\/7 and its highest-category Day 1 High Risk, issued only 3-4 times per decade, signifies the potential for a major historic severe weather outbreak.\"\n      }\n    }\n  ]\n}\n<\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Looking up the Saffir-Simpson hurricane scale, the difference between a severe thunderstorm warning vs tornado warning, what a supercell is, or what a storm surge warning or snow squall warning means for your safety?<span class=\"more\"> <a href=\"https:\/\/ialert.com\/blog\/weather-articles\/weather-glossary\/glossary-of-weather-terms-beginning-with-s\/\">Read More&#8230;<\/a><\/span><\/p>\n","protected":false},"author":6,"featured_media":4918,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[397],"tags":[386,396,395,398,394],"class_list":["post-1603","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-weather-glossary","tag-glossary","tag-meteorology-glossary","tag-meteorology-terms","tag-weather-glossary-2","tag-weather-terms"],"acf":[],"_links":{"self":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/1603","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/comments?post=1603"}],"version-history":[{"count":9,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/1603\/revisions"}],"predecessor-version":[{"id":4919,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/1603\/revisions\/4919"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/media\/4918"}],"wp:attachment":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/media?parent=1603"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/categories?post=1603"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/tags?post=1603"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}