vania-janet/multiturn-rag-retrieval-data huggingface dataset:
Thunderstorm
Forms of MCS that develop in the tropics are found in use either the Intertropical Convergence Zone or monsoon troughs , generally within the warm season between spring and fall . More intense systems form over land than over water . One exception is that of lake - effect snow bands , which form due to cold air moving across relatively warm bodies of water , and occurs from fall through spring . Polar lows are a second special class of MCS . They form at high latitudes during the cold season . Once the parent MCS dies , later thunderstorm development can occur in connection with its remnant mesoscale convective vortex ( MCV ) . Mesoscale convective systems are important to the United States rainfall climatology over the Great Plains since they bring the region about half of their annual warm season rainfall .
1935 Labor Day hurricane
The 1935 Labor Day Hurricane was the most intense hurricane to make landfall in the United States on record and the most intense Atlantic hurricane until Hurricane Gilbert . The second tropical cyclone , second hurricane , and second major hurricane of the 1935 Atlantic hurricane season , the Labor Day Hurricane was the first of three Category 5 hurricanes to strike the United States at that intensity during the 20th century ( the other two being 1969 's Hurricane Camille and 1992 's Hurricane Andrew ) . After forming as a weak tropical storm east of the Bahamas on August 29 , it slowly proceeded westward and became a hurricane on September 1 .
San Francisco fog
Under normal summertime conditions , a daily pattern of fog and low clouds occurs . Morning sun heats the ground which in turn heats the marine layer over the land areas . This creates convective turbulence within the marine layer as well as evaporation of any clouds within it . The marine layer clears back toward the coast , usually by noon . By mid-afternoon , inland areas have heated sufficiently to decrease the air pressure and increase the onshore flow . By late afternoon , the wind increases and begins to cool the onshore marine layer , allowing the fog and low clouds offshore to progress inland without evaporating . Cloudiness streams in over the Bay and through the various gaps . How far the clouds can penetrate inland depends on the depth of the marine layer and the strength of the cooling winds . As night falls and inland areas cool down , the winds usually decrease , but the fog and clouds remain wherever they have blown in until the following morning when the cycle repeats .
Caribbean Sea
The Caribbean weather is influenced by the Gulf Stream and Humboldt Current ocean currents . The tropical location of the sea helps the water to maintain a warm temperature ranging from the low of 21 -- 26 ° C ( 70 -- 79 ° F ) by the season .
Gun laws in North Carolina
5 . Areas of Emergency and Riots Pursuant to North Carolina 's Emergency Management Act ( Chapter 166A of the General Statutes ) local governments may impose restrictions on dangerous weapons such as explosives , incendiary devices , and radioactive materials and devices when a state of emergency is declared but may not impose restrictions on lawfully possessed firearms .
Kenya
The `` long rains '' season occurs from March / April to May / June . The `` short rains '' season occurs from October to November / December . The rainfall is sometimes heavy and often falls in the afternoons and evenings . The temperature remains high throughout these months of tropical rain . The hottest period is February and March , leading into the season of the long rains , and the coldest is in July , until mid August . A
Vermont
The state suffered severe flooding in late August 2011 caused by Tropical Storm Irene . Heavy rains caused flooding in many towns built in narrow river valleys . The governor described it as one of the worst natural disasters of the 20th and 21st centuries , second only to the flood of 1927 . Political
Great Salt Lake
The lake effect snowfalls are more likely to occur in late fall , early winter , and during spring due to the higher temperature differences between the lake and the air above it . During summer , the temperature differences can cause thunderstorms to form over the lake and drift eastward along the northern Wasatch Front . Some rainstorms may also be partially attributed to the lake effect in fall and spring . It is estimated that approximately six to eight lake effect snowstorms occur in a year , and that 10 % of the average precipitation of Salt Lake City can be attributed to the lake effect .
Hurricane Hugo
Hurricane Hugo Category 5 major hurricane ( SSHWS / NWS ) Hurricane Hugo approaching South Carolina on September 21 Formed September 10 , 1989 Dissipated September 25 , 1989 ( Extratropical after September 22 ) Highest winds 1 - minute sustained : 160 mph ( 260 km / h ) Lowest pressure 918 mbar ( hPa ) ; 27.11 inHg Fatalities 100 total ( estimated ) Damage $10 billion ( 1989 USD ) Areas affected Cape Verde , Lesser Antilles , Puerto Rico , Hispaniola , Turks and Caicos Islands , Bahamas , East Coast of the United States , Atlantic Canada , U.S. Virgin Islands Part of the 1989 Atlantic hurricane season
Atlantic hurricane season
Year Map Number of tropical storms Number of hurricanes Number of major hurricanes Deaths Damage USD Strongest storm Major landfall hurricanes Notes 1910 5 100 $1.25 million `` Cuba '' The Great Cuba Hurricane of 1910 ( cat 4 ) 1911 6 0 27 $3 million Three 1912 7 116 $67,000 Seven The Jamaica Hurricane of 1912 ( cat 3 ) 1913 6 0 5 $4 million Four 1914 0 0 0 Unknown One Least active season on record . One of two seasons with no recorded hurricanes . 1915 6 5 675 $63 million `` New Orleans '' Great Galveston Hurricane of 1915 ( cat 4 ) New Orleans Hurricanes of 1915 ( cat 4 ) Two cat 4 hurricanes made landfall in US in same year . Galveston last struck with major hurricane in 1900 . 1916 15 10 5 31 $5.9 million `` Texas '' Gulf Coast Hurricane of 1916 ( cat 3 ) Charleston Hurricane of 1916 ( cat 3 ) Great Texas Hurricane of 1916 ( cat 4 ) 3 major hurricanes made landfall this year following a very active 1915 season . 1917 5 $170,000 `` Nueva Gerona '' Nueva Gerona Hurricane of 1917 ( cat 4 ) 1918 6 34 $5 + million One Louisiana Hurricane of 1918 ( cat 3 ) 1919 5 ~ 900 $22 million `` Florida Keys '' Great Florida Keys Hurricane of 1919 ( cat 4 )
Hurricane Irma
On September 4 , after moving into more favorable conditions , Irma strengthened into a Category 4 hurricane . As it continued approaching the Leeward Islands , Irma underwent a second and more robust period of rapid intensification , becoming a Category 5 hurricane by 12 : 00 UTC on the following day , with winds of 175 mph ( 280 km / h ) . As it began to take on annular characteristics , the extremely powerful hurricane continued to intensify , with maximum sustained winds peaking at 180 mph ( 285 km / h ) near 18 : 00 UTC on September 5 -- although it was operationally assessed at 185 mph ( 295 km / h ) . Eight hours later , Irma made landfall along the northern coast of Barbuda near peak strength . Later that day , around 18 : 00 UTC , the storm 's pressure bottomed out at 914 mbar ( 27.0 inHg ) -- this was the lowest in the Atlantic since Dean in 2007 . While maintaining its intensity , Irma made successive landfalls on September 6 , at 11 : 15 UTC on Sint Maarten , and at 16 : 30 UTC on Virgin Gorda , in the British Virgin Islands , all while it was at peak intensity . Three
Climate of Alabama
Sometimes tornadoes occur -- these are common throughout the state , although the peak season for tornadoes varies from the northern to southern parts of the state . Alabama , along with Kansas , has the most reported EF5 tornadoes than any other state -- according to statistics from the National Climatic Data Center for the period January 1 , 1950 , to October 31 , 2006 . An F5 tornado is the most powerful of its kind . Several long -- tracked F5 tornadoes have contributed to Alabama reporting more tornado fatalities than any other state except for Texas and Mississippi . The Super Outbreaks of April 1974 and April 2011 both badly affected Alabama . The northern part of the state -- along the Tennessee Valley -- is one of the areas in the US most vulnerable to violent tornadoes . The area of Alabama and Mississippi most affected by tornadoes is sometimes referred to as Dixie Alley , as distinct from the Tornado Alley of the Southern Plains . Alabama is one of the few places in the world that has a secondary tornado season ( November and December ) along with the spring severe weather season .
Climate of the United Kingdom
The high latitude and proximity to a large ocean to the west means that the United Kingdom experiences strong winds . The prevailing wind is from the south - west , but it may blow from any direction for sustained periods of time . Winds are strongest near westerly facing coasts and exposed headlands .
Climate of Florida
There are more tornadoes per square mile in Florida than any other state . However , these tornadoes tend to be much weaker and short - lived than in other states like the Midwest or Great Plains . Strong tornadoes do occasionally form in Florida , usually in conjunctions with a cold frontal passage in the winter or spring . A total of 42 people died in February 1998 from the deadliest such tornado outbreak in Central Florida , which occurred during the nighttime hours .
Geography of Illinois
Tornadoes are a common hazard , primarily in the central part of the state , with peak months in June and April . Freezing rain is most common in central Illinois .
Thunderstorm
In North America , hail is most common in the area where Colorado , Nebraska , and Wyoming meet , known as `` Hail Alley . '' Hail in this region occurs between the months of March and October during the afternoon and evening hours , with the bulk of the occurrences from May through September . Cheyenne , Wyoming is North America 's most hail - prone city with an average of nine to ten hailstorms per season . In South America , areas prone to hail are cities like Bogotá , Colombia .
Thunderstorm
This is the most common type of thunderstorm development . Mature thunderstorms are found near the center of the cluster , while dissipating thunderstorms exist on their downwind side . Multicell storms form as clusters of storms but may then evolve into one or more squall lines . While each cell of the cluster may only last 20 minutes , the cluster itself may persist for hours at a time . They often arise from convective updrafts in or near mountain ranges and linear weather boundaries , such as strong cold fronts or troughs of low pressure . These type of storms are stronger than the single - cell storm , yet much weaker than the supercell storm . Hazards with the multicell cluster include moderate - sized hail , flash flooding , and weak tornadoes .
Season
Regardless of the time of year , the northern and southern hemispheres always experience opposite seasons . This is because during summer or winter , one part of the planet is more directly exposed to the rays of the Sun ( see Fig. 1 ) than the other , and this exposure alternates as the Earth revolves in its orbit . For approximately half of the year ( from around March 20 to around September 22 ) , the Northern Hemisphere tips toward the Sun , with the maximum amount occurring on about June 21 . For the other half of the year , the same happens , but in the Southern Hemisphere instead of the Northern , with the maximum around December 21 . The two instants when the Sun is directly overhead at the Equator are the equinoxes . Also at that moment , both the North Pole and the South Pole of the Earth are just on the terminator , and hence day and night are equally divided between the two hemispheres . Around the March equinox , the Northern Hemisphere will be experiencing spring as the hours of daylight increase , and the Southern Hemisphere is experiencing autumn as daylight hours shorten .
Austin, Texas
Typical of Central Texas , severe weather in Austin is a threat that can strike during any season . However , it is most common during the spring . According to most classifications , Austin lies within the extreme southern periphery of Tornado Alley , although many sources place Austin outside of Tornado Alley altogether . Consequently , tornadoes strike Austin less frequently than areas farther to the north . However , severe weather and / or supercell thunderstorms can occur multiple times per year , bringing damaging winds , lightning , heavy rain , and occasional flash flooding to the city . The deadliest storm to ever strike city limits was the twin tornadoes storm of May 4 , 1922 , while the deadliest tornado outbreak to ever strike the metro area was the Central Texas tornado outbreak of May 27 , 1997 .
Oklahoma
Oklahoma is in a humid subtropical region . Oklahoma lies in a transition zone between humid continental climate to the north , semi-arid climate to the west , and humid subtropical climate in the central , south and eastern portions of the state . Most of the state lies in an area known as Tornado Alley characterized by frequent interaction between cold , dry air from Canada , warm to hot , dry air from Mexico and the Southwestern U.S. , and warm , moist air from the Gulf of Mexico . The interactions between these three contrasting air currents produces severe weather ( severe thunderstorms , damaging thunderstorm winds , large hail and tornadoes ) with a frequency virtually unseen anywhere else on planet Earth . An average 62 tornadoes strike the state per year -- one of the highest rates in the world .
Thunderstorm
This term technically applies to a single thunderstorm with one main updraft . Also known as air - mass thunderstorms , these are the typical summer thunderstorms in many temperate locales . They also occur in the cool unstable air that often follows the passage of a cold front from the sea during winter . Within a cluster of thunderstorms , the term `` cell '' refers to each separate principal updraft . Thunderstorm cells occasionally form in isolation , as the occurrence of one thunderstorm can develop an outflow boundary that sets up new thunderstorm development . Such storms are rarely severe and are a result of local atmospheric instability ; hence the term `` air mass thunderstorm '' . When such storms have a brief period of severe weather associated with them , it is known as a pulse severe storm . Pulse severe storms are poorly organized and occur randomly in time and space , making them difficult to forecast . Single - cell thunderstorms normally last 20 -- 30 minutes .
Thunderstorm
A squall line is an elongated line of severe thunderstorms that can form along or ahead of a cold front . In the early 20th century , the term was used as a synonym for cold front . The squall line contains heavy precipitation , hail , frequent lightning , strong straight line winds , and possibly tornadoes and waterspouts . Severe weather in the form of strong straight - line winds can be expected in areas where the squall line itself is in the shape of a bow echo , within the portion of the line that bows out the most . Tornadoes can be found along waves within a line echo wave pattern , or LEWP , where mesoscale low pressure areas are present . Some bow echoes in the summer are called derechos , and move quite fast through large sections of territory . On the back edge of the rain shield associated with mature squall lines , a wake low can form , which is a mesoscale low pressure area that forms behind the mesoscale high pressure system normally present under the rain canopy , which are sometimes associated with a heat burst . This kind of storm is also known as `` Wind of the Stony Lake '' ( Traditional Chinese : 石 湖 風 -- shi2 hu2 feng1 , Simplified Chinese : 石 湖 风 ) in southern China .
Climate of the United Kingdom
Autumn in the United Kingdom lasts from September to November . The season is notorious for being unsettled -- as cool polar air moves southwards following the sun , it meets the warm air of the tropics and produces an area of great disturbance along which the country lies . This combined with the warm ocean due to heating throughout the spring and summer , produces the unsettled weather of autumn . In addition , when the air is particularly cold temperatures on land may be colder than the ocean , resulting in significant amounts of condensation and clouds which bring rain to the country .
Thunderstorm
Organized thunderstorms and thunderstorm clusters / lines can have longer life cycles as they form in environments of significant vertical wind shear , normally greater than 25 knots ( 13 m / s ) in the lowest 6 kilometres ( 3.7 mi ) of the troposphere , which aids the development of stronger updrafts as well as various forms of severe weather . The supercell is the strongest of the thunderstorms , most commonly associated with large hail , high winds , and tornado formation . Precipitable water values of greater than 31.8 millimetres ( 1.25 in ) favor the development of organized thunderstorm complexes . Those with heavy rainfall normally have precipitable water values greater than 36.9 millimetres ( 1.45 in ) . Upstream values of CAPE of greater than 800 J / kg are usually required for the development of organized convection .
Climate of Florida
While tornadoes in the Midwest are more severe , a higher rate of deaths are experienced in Florida , and Brevard County , specifically , due to higher population density and quantity of manufactured homes .
Season
Calendar - based reckoning defines the seasons in absolute rather than relative terms . Accordingly , if floral activity is regularly observed during the coolest quarter of the year in a particular area , it is still considered winter despite the traditional association of flowers with spring and summer . Additionally , the seasons are considered to change on the same dates everywhere that uses a particular calendar method regardless of variations in climate from one area to another . Most calendar - based methods use a four - season model to identify the warmest and coldest seasons , which are separated by two intermediate seasons .
Climate of the United Kingdom
Thunderstorms are most common in southern and eastern England , and least common in the north and west . In London , thunderstorms occur on average 14 -- 19 days a year , while in most of Northern Ireland and the west of Scotland thunderstorms occur on around 3 days a year . Occasionally , thunderstorms can be severe and produce large hailstones as seen in Ottery St Mary , Devon in October 2008 , where drifts reached 1.8 metres ( 5 ft 11 in ) .
Season
In Sweden and Finland , meteorologists use a non-calendar based definition for the seasons based on the temperature . Spring begins when the daily averaged temperature permanently rises above 0 ° C , summer begins when the temperature permanently rises above + 10 ° C , summer ends when the temperature permanently falls below + 10 ° C and winter begins when the temperature permanently falls below 0 ° C. `` Permanently '' here means that the daily averaged temperature has remained above or below the limit for seven consecutive days . This implies two things : first , the seasons do not begin at fixed dates but must be determined by observation and are known only after the fact ; and second , a new season begins at different dates in different parts of the country . In Great Britain , the onset of spring used to be defined as when the maximum daily temperature reached 50 ° F ( 10 ° C ) in a defined sequence of days . This almost always occurred in March . However , with global warming this temperature is now not uncommon in the winter .
United States
The United States , with its large size and geographic variety , includes most climate types . To the east of the 100th meridian , the climate ranges from humid continental in the north to humid subtropical in the south . The Great Plains west of the 100th meridian are semi-arid . Much of the Western mountains have an alpine climate . The climate is arid in the Great Basin , desert in the Southwest , Mediterranean in coastal California , and oceanic in coastal Oregon and Washington and southern Alaska . Most of Alaska is subarctic or polar . Hawaii and the southern tip of Florida are tropical , as are the populated territories in the Caribbean and the Pacific . Extreme weather is not uncommon -- the states bordering the Gulf of Mexico are prone to hurricanes , and most of the world 's tornadoes occur within the country , mainly in Tornado Alley areas in the Midwest and South .
Thunderstorm
In more contemporary times , thunderstorms have taken on the role of a scientific curiosity . Every spring , storm chasers head to the Great Plains of the United States and the Canadian Prairies to explore the scientific aspects of storms and tornadoes through use of videotaping . Radio pulses produced by cosmic rays are being used to study how electric charges develop within thunderstorms . More organized meteorological projects such as VORTEX2 use an array of sensors , such as the Doppler on Wheels , vehicles with mounted automated weather stations , weather balloons , and unmanned aircraft to investigate thunderstorms expected to produce severe weather . Lightning is detected remotely using sensors that detect cloud - to - ground lightning strokes with 95 percent accuracy in detection and within 250 metres ( 820 ft ) of their point of origin .
Season
The seasonal cycle in the polar and temperate zones of one hemisphere is opposite to that of the other . When it is summer in the Northern Hemisphere , it is winter in the Southern , and vice versa .
Michigan
The entire state averages 30 days of thunderstorm activity per year . These can be severe , especially in the southern part of the state . The state averages 17 tornadoes per year , which are more common in the extreme southern portion of the state . Portions of the southern border have been almost as vulnerable historically as states further west and in Tornado Alley . For this reason , many communities in the very southern portions of the state are equipped with tornado sirens to warn residents of approaching tornadoes . Farther north , in Central Michigan , Northern Michigan , and the Upper Peninsula , tornadoes are rare .
Ottawa
Spring and fall are variable , prone to extremes in temperature and unpredictable swings in conditions . Hot days above 30 ° C ( 86 ° F ) have occurred as early as April or as late as October . Annual precipitation averages around 940 millimetres ( 37 in ) .
Thunderstorm
There are four main types of thunderstorms : single - cell , multi-cell , squall line ( also called multi-cell line ) and supercell . Which type forms depends on the instability and relative wind conditions at different layers of the atmosphere ( `` wind shear '' ) . Single - cell thunderstorms form in environments of low vertical wind shear and last only 20 -- 30 minutes .
Season
In meteorological terms , the solstices ( the maximum and minimum insolation ) do not fall in the middles of summer and winter . The heights of these seasons occur up to 7 weeks later because of seasonal lag . Seasons , though , are not always defined in meteorological terms .
Hurricane Katrina
The storm also brought heavy rains with 8 -- 10 inches ( 200 -- 250 mm ) falling in southwestern Mississippi and rain in excess of 4 inches ( 100 mm ) falling throughout the majority of the state . Katrina caused eleven tornadoes in Mississippi on August 29 , some of which damaged trees and power lines .
Climate of Florida
Long term forecasts are made based on these effects . However , they are easily overridden , in winter , by the Arctic oscillation and North Atlantic oscillations , which can only be predicted about two weeks in advance . These can drop the temperature noticeably from seasonal norms .