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Imelda’s Remnants Cause Flash Floods in Southeast Texas

The remnants of former Tropical Storm Imelda caused flash floods over parts of southeastern Texas on Thursday.  The National Weather Service extended Flash Flood Emergencies for portions of southwestern San Jacinto County, east central Montgomery County, Chambers County and Liberty County.

At 11:00 a.m. EDT on Thursday the center of Tropical Depression Imelda was located at latitude 30.5°N and longitude 95.5°W which put it about 55 miles (90 km) north of Houston, Texas.  Imelda was moving toward the northwest at 6 m.p.h. (9 km/h).  The maximum sustained wind speed was 25 m.p.h. (40 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1009 mb.

The remnants of former Tropical Storm Imelda remained nearly stationary over southeastern Texas on Thursday morning.  Bands of showers and thunderstorms in the eastern half of the circulation were dropping heavy rain.  There were unofficial reports that some locations had received up to 30 inches (0.9 meters) of rain.  Flash flood were occurring and a portion of Interstate 10 was closed due to high water.  Southeasterly winds were transport very moist air over the region and the heavy rain was forecast to continue.

Elsewhere over the Atlantic Ocean, former Tropical Storm Jerry strengthened into a hurricane and Hurricane Humberto sped away from Bermuda.  At 11:00 a.m. EDT on Thursday the center of Hurricane Jerry was located at latitude 16.8°N and longitude 54.4°W which put it about 490 miles (785 km) east of the Leeward Islands.  Jerry was moving toward the west-northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 988 mb.  Tropical Storm Watches were in effect for St. Maarten, St. Martin, St. Barthelemy, Barbuda, Anguilla, Saba and St. Eustatius.

At 11:00 a.m. EDT on Thursday the center of Hurricane Humberto was located at latitude 36.8°N and longitude 60.0°W which put it about 415 miles (665 km) northeast of Bermuda.  Humberto was moving toward the northeast at 24 m.p.h. (39 km/h).  The maximum sustained wind speed was 110 m.p.h. (185 km/h) and there were gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 955 mb.

Hurricane Humberto Brings Strong Winds to Bermuda

Hurricane Humberto brought strong winds to Bermuda on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Humberto was located at latitude 34.0°N and longitude 63.9°W which put it about 130 miles (215 km) northeast of Bermuda.  Humberto was moving toward the northeast at 23 m.p.h. (37 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 952 mb.

The Hurricane Warning for Bermuda was changed to a Tropical Storm Warning because Hurricane Humberto was moving rapidly away from Bermuda.

Although the center of Hurricane Humberto passed just to the northwest of Bermuda, Humberto did produce hurricane force winds on Bermuda.  The weather station at the L.F. Wade International airport measured a sustained wind speed of 82 m.p.h. (132 km/h) and a wind gust to 114 m.p.h. (184 km/h).  There were reports of power electrical outages and wind damage on Bermuda.  Conditions will improve on Thursday when Hurricane Humberto moves rapidly away from Bermuda.

A trough over the eastern U.S. will steer Hurricane Humberto rapidly toward the northeast on Thursday.  Humberto will move into a less favorable environment.  The upper level trough will cause moderate vertical wind shear.  Hurricane Humberto will start to move over cooler water.  Moderate shear and cooler water will cause Hurricane Humberto to weaken during the next several days.  While Humberto moves into a less tropical environment, it will make a transition to a strong extratropical cyclone.

Elsewhere, Tropical Depression Imelda continued to drop heavy rain over parts of eastern Texas and southwestern Louisiana and Tropical Storm Jerry threatened the northern Leeward Islands.  At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Imelda was located at latitude 31.2°N and longitude 94.9°W which put it about 110 miles (175 km) north-northeast of Houston, Texas.  Imelda was moving toward the north at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1008 mb.

At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Jerry was located at latitude 15.4°N and longitude 51.8°W which put it about 675 miles (1085 km) east of the Leeward Islands.  Jerry was moving toward the west-northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 997 mb.  Tropical Storm Watches were in effect for St. Maarten, St. Martin, St. Barthelemy, Barbuda, Anguilla, Saba and St. Eustatius.

Tropical Storm Jerry Strengthens East of Leeward Islands

Tropical Storm Jerry strengthened east of the Leeward Islands on Wednesday.  At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Jerry was located at latitude 14.6°N and longitude 49.2°W which put it about 855 miles east of the Leeward Islands.  Jerry was moving toward the west-northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 1002 mb.

The circulation around Tropical Storm Jerry exhibited much more organization on Wednesday.  A long band of thunderstorms curved around the western and southern sides of the center of circulations.  Other bands of showers and thunderstorms developed and began to revolve around the center of circulation.  Storms near the center began to generate upper level divergence which was pumping mass away from the tropical storm.  Winds to tropical storm force extended out about 45 miles (75 km) from the center of circulation.

Tropical Storm Jerry will move through an environment favorable for intensification during the next several days.  Jerry will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Jerry is likely to strengthen into a hurricane during the next day or two.  Jerry could rapidly intensify once it develops an inner core with an eye and an eyewall.

Tropical Storm Jerry will move south of a subtropical ridge over the Atlantic Ocean.  The ridge will steer Jerry toward the west-northwest.  On its anticipated track Tropical Storm Jerry could approach the northern Leeward Islands on Friday.  Jerry is likely to be a hurricane by that time.

Elsewhere, Hurricane Humberto was nearing Bermuda and Tropical Depression Imelda was dropping heavy rain over parts of eastern Texas and southwestern Louisiana.  At 2:00 p.m. EDT on Wednesday the center of Hurricane Humberto was located at latitude 32.4°N and longitude 67.2°W which put it about 140 miles (225 km) west of Bermuda.  Humberto was moving toward the east-northeast at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 952 mb.  A Hurricane Warning was in effect for Bermuda.

At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Imelda was located at latitude 30.6°N and longitude 95.6°W which put it about 65 miles (105 km) north of Houston, Texas.  Imelda was moving toward the north at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1009 mb.  Flash Flood Watches were in effect for parts of eastern Texas and southwestern Louisiana.

Hurricane Humberto Strengthens to a Major Hurricane, Warning for Bermuda

Hurricane Humberto strengthened into a major hurricane on Tuesday and a Hurricane Warning was issued for Bermuda.  At 11:00 pm. EDT on Tuesday the center of Hurricane Humberto was located at latitude 31.3°N and longitude 71.0°W which put it about 370 miles (595 km) west of Bermuda.  Humberto was moving toward the east-northeast at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 951 mb.

Hurricane Humberto exhibited the structure of a large mature hurricane on Tuesday night.  There was a circular eye at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Humberto.  The stronger rainbands were occurring in the northern half of the circulation.  Humberto appeared to be drawing drier air around the southern half of the circulation and bands in that part of the hurricane consisted primarily of showers and lower clouds.

Winds to hurricane force extended out about 45 miles (75 km) from the center of Hurricane Humberto.  Winds to tropical storm force extended out about 150 miles (240 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Humberto was 20.6.  The Hurricane Size Index (HSI) was 16.9 and the Hurricane Wind Intensity Size Index (HWISI) was 37.5.  Hurricane Humberto was capable of causing major wind damage.

Hurricane Humberto will remain in an environment capable of supporting a major hurricane for another 12 to 24 hours.  Humberto will move over water where the Sea Surface Temperature is near 28.5°C.  An upper level trough over the eastern U.S. will produce southwesterly winds which will blow toward the top of the hurricane.  Those winds will cause some vertical wind shear, but the shear may not be strong enough to cause Hurricane Humberto to weaken on Wednesday.

Hurricane Humberto will move around the northern side of a subtropical high pressure system over the Atlantic Ocean.  The high and the upper level trough over the eastern U.S.  will combine to steer Humberto toward the east-northeast on Wednesday.  On its anticipated track the center of Hurricane Humberto could approach Bermuda on Wednesday evening.  Humberto could still be a major hurricane at that time.  If the center of Hurricane Humberto passes just north of Bermuda, then the strongest winds could affect Bermuda.

Elsewhere, Tropical Depression Imelda was dropping heavy rain near Houston, Texas and Tropical Depression Ten was churning toward the northern Leeward Islands.  At 11:00 p.m. EDT on Tuesday the center of Tropical Depression Imelda was located at latitude 29.8°N and longitude 95.5°W which put it about 10 miles (15 km) northwest of Houston, Texas.  Imelda was moving toward the north at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there  were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1007 mb.

At 11:00 p.m. EDT on Tuesday the center of Tropical Depression Ten was located at latitude 13.7°N and longitude 46.7°W which put it about 1030 miles (1660 km) east of the Leeward Islands.  It was moving toward the west-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1006 mb.

Tropical Storm Imelda Forms Along Upper Texas Coast

Tropical Storm Imelda formed along the Upper Texas coast on Tuesday.  At 2:00 p.m. EDT on Tuesday the center of Tropical Storm Imelda was located at latitude 29.0°N and longitude 95.3°W which put it near Freeport, Texas.  Imelda was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1005 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Sargent to Port Bolivar, Texas.

A small low pressure system over the northwestern Gulf of Mexico exhibited greater organization on satellite and radar images on Tuesday.  When a surface weather station reported a sustained wind speed of 40 m.p.h. (65 km/h), the National Hurricane Center designated the system as Tropical Storm Imelda.  The winds to tropical storm force were occurring southeast of the center of circulation.  Winds to tropical storm force extended out about 45 miles (75 km) in the southeastern quadrant of Tropical Storm Imelda.

Tropical Storm Imelda will move around the western end of a warm high pressure system over the southeastern U.S.  The high will steer Imelda slowly toward the north during the next several days.  On its anticipated track Tropical Storm Imelda will move slowly inland over east Texas.  Although Imelda will cause a small storm surge along the coast around the northwestern Gulf of Mexico, locally heavy rain will pose a much greater risk.  Southeasterly winds blowing around the eastern side of Tropical Storm Imelda will transport very moist air over parts of eastern Texas.  Over a foot of rain (0.33 meters) could fall in some locations where rain bands linger.  Flash Flood Watches have been issued for a number of counties around Houston and Galveston.

Elsewhere over the Atlantic Ocean, Hurricane Humberto moved closer to Bermuda and Tropical Depression Ten formed east of the Lesser Antilles.  At 2:00 p.m. EDT on Tuesday the center of Hurricane Humberto was located at latitude 30.8°N and longitude 72.9°W which put it about 490 miles (785 km) west-southwest of Bermuda.  Humberto was moving toward the east-northeast at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 961 mb.

A Hurricane Watch and a Tropical Storm Warning were in effect for Bermuda.

At 11:00 a.m. EDT on Tuesday the center of Tropical Depression Ten was located at latitude 12.9°N and longitude 44.9°W which put it about 1165 miles (1870 km) east-southeast of the Leeward Islands.  It was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1007 mb.  The depression is forecast to strengthen into a hurricane while it moves toward the northern Leeward Islands.

Tropical Storm Kirk Forms South of the Cabo Verde Islands

Tropical Storm Kirk formed south of the Cabo Verde Islands on Saturday.  At 11:00 a.m. EDT on Saturday the center of Tropical Storm Kirk was located at latitude 8.3°N and longitude 23.6°W which put it about 450 miles (730 km) south of the Cabo Verde Islands.  Kirk was moving toward the west at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1005 mb.

The circulation around Tropical Storm Kirk is large and not well organized.  There is a low level center of circulation, but there are not many thunderstorms near the center.  There were thunderstorms in a cluster west of the center and more thunderstorms were in another cluster east of the center.  Some of the thunderstorms appeared to be organizing into bands, but the bands were not well developed.

Tropical Storm Kirk will move through an environment during the next day or two that should be favorable for intensification.  Kirk will move over water where the Sea Surface Temperature is near 27°C.  It will move through an area where the upper level winds are weak and the wind shear will not be strong enough to prevent intensification.  Tropical Storm Kirk is likely to become more organized during the next 24 to 48 hours.  It will move into a region in a couple of days where the lower level easterly winds will be stronger vertical wind shear could increase.

Tropical Storm Kirk will move south of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Kirk toward the west at a fairly quick pace.  On its anticipated track Tropical Storm Kirk could approach the Lesser Antilles by late next week.

Elsewhere over the tropical Atlantic, Tropical Depression Eleven moved slowly toward the Windward Islands.  At 11:00 a.m. EDT on Saturday the center of Tropical Depression Eleven was located at latitude 13.2°N and longitude 53.8°W which put it about 485 miles (780 km) east of the Windward Islands.  It was moving toward the west at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1008 mb.

Tropical Depression Eleven Forms East of the Windward Islands

Tropical Depression Eleven formed east of the Windward Islands on Friday night.  At 11:00 p.m. EDT on Friday the center of Tropical Depression Eleven was located at latitude 13.1°N and longitude 53.4°W which put it about 510 miles (825 km) east of the Windward Islands.  It was moving toward the west-northwest at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1007 mb.

A small circular low pressure system within a tropical wave has been moving westward toward the Windward Islands.  An upper level trough near the eastern Caribbean Sea has been producing southwesterly winds which blowing across the top of the low.  Those winds were producing significant vertical wind shear and they were preventing taller thunderstorms from persisting near the center of circulation.  The National Hurricane Center decided that the low pressure system possessed sufficient convection to be classified as a Tropical Depression at 11:00 p.m.. EDT on Friday night.

The distribution of thunderstorms around Tropical Depression Eleven was still asymmetrical because of the wind shear caused by the upper level trough.  There was a well defined, but small, low level circulation with a distinct center.  Most of the bands around the center of circulation consisted of showers and lower clouds.  There were stronger thunderstorms in some of the bands east of the center of circulation.

Tropical Depression Eleven will move through an environment somewhat favorable for intensification.  It will move over water where the Sea Surface Temperature is near 29°C.  The upper level trough will continue to cause significant vertical wind shear.  The wind shear will limit the potential for intensification.  Tropical Depression Eleven could strengthen into a tropical storm, but rapid intensification is not likely.  However, small tropical cyclones can strengthen or weaken very rapidly if the environment around them changes.

Tropical Depression Eleven will move south of the subtropical high pressure system over the Atlantic Ocean.  The high will steer the depression in a west-northwesterly direction.  On its anticipated track the center of Tropical Depression Eleven could be east of the Lesser Antilles on Sunday night.

Tropical Storm Irma Still Bringing Gusty Winds and Storm Surges to Southeast U.S.

Tropical Storm Irma was still bringing gusty winds, locally heavy rain and storm surges to parts of the Southeastern U.S. on Monday afternoon.  Gusty winds were blowing down trees and bringing down power lines in parts of Florida, Georgia, South Carolina and North Carolina.  Locally heavy rainfall resulted in the issuance of Flood Watches and Warnings for portions of those states.  Strong winds were blowing water toward the coast in northeastern Florida, Georgia and South Carolina.  Storm surges caused flooding in Jacksonville, Florida and Savannah, Georgia.  The water level at Charleston, South Carolina was higher than it was during Hurricane Matthew in 2016.

At 5:00 p.m. EDT on Monday the center of Tropical Storm Irma was located at latitude 31.5°N and longitude 84.0°W which put it about 10 miles (15 km) east of Albany, Georgia.  Irma was moving toward the north-northwest at 17 m.p.h.  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 985 mb.

A Tropical Storm Warning remained in effect for the portion of the coast from Altamaha Sound to South Santee River.

The structure of Tropical Storm Irma evolved as it moved further inland.  Drier air wrapped around the  western side of the circulation.  Convergence between a large surface high north of Irma and the tropical storm produced heavy rain northeast of the center of circulation.  The heaviest rain fell over Georgia, South Carolina and the western half of North Carolina.  The northern edge of the rain shield was moving over Tennessee and southeast Kentucky.  The pressure difference between the high and Irma also generated strong winds in the eastern half of Irma’s circulation.  Those strong winds pushed water toward the coast in northern Florida, Georgia and South Carolina.  The wind caused storm surges of up to 10 feet (3 meters) in some locations.  Water was reported in parts of downtown Jacksonville, Florida and Charleston, South Carolina.

Tropical Storm Irma will continue to move toward the north-northwest and weaken.  The circulation of Irma is very large, and it will take a few more days to spin completely.  There could be stronger winds in the high elevations of Appalachian Mountains.  Locally heavy rain could also create the potential for floods in some valleys.  The storm surges along the coast should gradually subside as the wind speeds decrease.

Elsewhere, Hurricane Jose was moving northward east of the Bahamas.  At 5:00 p.m. EDT on Monday the center of Hurricane Jose was located at latitude 31.5°N and longitude 84.0°W which put it about 555 miles (895 km) east of Nassau, Bahamas.  Jose was moving toward the north at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 973 mb.  Hurricane Jose is forecast to make a slow clockwise loop this week.  On it anticipated track Hurricane Jose could still be east of the Bahamas at the end of the week.

Hurricane Irma Makes Landfall on Marco Island, Florida

The center of Hurricane Irma made landfall on the coast at Marco Island, Florida on Sunday afternoon.  The Marco Island Emergency Operations Center reported a wind gust to 135 m.p.h. (217 km/h) when the northern portion of the eyewall passed over.  The airport at Naples, Florida reported sustained winds to 88 m.p.h. (142 km/h) and wind gusts to 135 m.p.h. (217 km/h).

At 5:00 p.m. EDT on Sunday the center of Hurricane Irma was located at latitude 26.2°N and longitude 81.8°W which put it about 5 miles (10 km) north of Naples, Florida.  Irma was moving toward the north at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 938 mb.

A Hurricane Warning was in effect for the portion of the coast from Fernandina Beach to Indian Pass, Florida including the Florida Keys and Lake Okeechobee.  A Hurricane Watch was in effect from Fernandina Beach, Florida to Edisto Beach, South Carolina.  A Tropical Storm Warning was in effect for the portion of the coast from Fernandina Beach, Florida to the South Santee River, South Carolina and from Indian Pass, Florida to the Okaloosa/Walton County line.  A Tropical Storm Watch was in effect for Bimini and Grand Bahama Island.

The intensity of Hurricane Irma decreased gradually on Sunday.  The hurricane began to pull in some drier air over the southeastern U.S. into the west side of the circulation.  In addition an upper level trough over the eastern U.S. caused an increase in the vertical wind shear.  The drier air and increased shear also produced a more asymmetrical wind field around Hurricane Irma.  The area of stronger winds was much larger in the eastern half of the circulation than it was on the western half of the circulation.  Winds to hurricane force extended out 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 220 miles (350 km) from the center.

Hurricane Irma will gradually weaken as it moves northward over Florida.  Irma is a large hurricane and it will spin down slowly.  Hurricane Irma will move steadily northward.  Irma is forecast to still be a hurricane when the center moves near Tampa and Central Florida.  Hurricane Irma is capable of causing widespread significant wind damage.  Isolated tornadoes could develop in thunderstorms in the outer rainbands.  Hurricane Irma will produce storm surges over a long section of the coast.  There was not much surge on the west coast of Florida on Sunday afternoon, because the winds were blowing the water away from the coast.  However, after the center moves north of an area, the wind will blow from the opposite direction and the water will rise quickly at the coast.  A station on the coast near Naples, Florida reported a water rise of six feet (two meters) in less than two hours after the center of Hurricane passed to the east.  Easterly winds on the eastern fringe of Hurricane Irma were blowing the water toward the coast and there were water rises from Miami, Florida to Charleston, South Carolina.  Strong southwesterly winds were still causing storm surges in the Florida Keys.  Hurricane Irma will also drop heavy rain over a prolonged period and it could cause freshwater flooding of rivers and streams.

Elsewhere over the tropical Atlantic Hurricane Jose moved away from the northern Leeward Islands on Sunday.  At 5:00 p.m. EDT om Sunday the center of Hurricane Jose was located at latitude 22.8°N and longitude 66.9°W which put it about 285 miles (455 km) east-northeast of Grand Turk Island.  Jose was moving toward northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  Hurricane Jose is forecast to stall over the tropical Atlantic east of the Bahamas and it could make a long slow loop during the next week.

Hurricane Irma Batters Florida Keys

Hurricane Irma battered the Florida Keys on Sunday morning.  At 9:00 a.m. EDT on Sunday morning the center of Hurricane Irma was located at latitude 24.5°N and longitude 81.5°W which put it about 30 miles (50 km) east-northeast of Key West, Florida.  Irma was moving toward the north-northwest at 8 m.p.h.  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  Hurricane Irma was a Category 4 hurricane on the Saffir-Simpson Scale.  The minimum surface pressure was 929 mb.

A Hurricane Warning was in effect for the portion of the coast from Fernandina Beach to Indian Pass, Florida including the Florida Keys and Lake Okeechobee.   A Hurricane Watch was in effect for the portion of the coast from Fernandina Beach, Florida to Edisto Beach, South Carolina.  A Tropical Storm Warning is in effect for the portion of the coast from Fernandina Beach to South Santee River, South Carolina and from Indian Pass to the Okaloosa/Walton County line.

A Hurricane Warning is in effect for the Cuban provinces of La Habana and Matanzas.  A Tropical Storm Watch is in effect for Bimini and Grand Bahama Island.

An outer eyewall started to wrap around the original eye of Hurricane Irma, but Irma did not go through an eyewall repacement cycle.  The original eyewall remained intact and the strongest winds were occurring in that eyewall.  The uncompleted formation of an outer eyewall did result in an increase in the size of Hurricane Irma.  Winds to hurricane force extend out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extend out over 200 miles (320 km) from the center.

The Hurricane Intensity Index (HII) for Hurricane Irma was 25.1.  The Hurricane Size Index (HSI) was 24.2 and the Hurricane Wind Intensity Size Index (HWISI) was 49.3.  Hurricane Irma is not quite as strong as Hurricane Charley was when Charley hit southwest Florida.  However, Hurricane Irma is much bigger than Charley was.  Hurricane Irma is stronger than Hurricane Wilma was when Wilma hit south Florida in 2005.  Irma is a little smaller than Wilma was.

Carysfort Reef Light near Key Largo reported a wind gust of 93 m.p.h. (150 km/h).  Hurricane Irma is causing winds to hurricane force over much of the Florida Keys.  Winds to tropical storm force are occurring in areas around Miami, Florida.

Hurricane Irma has turned toward the north.  The core of Hurricane Irma could make a landfall on the southwest coast of Florida between Everglades City and Naples, Florida later this afternoon.  Hurricane Irma could move northward near the west coast of Florida.  The center of Hurricane Irma could reach the Tampa/St. Petersburg area and Central Florida on Sunday night.

Hurricane Irma is large and dangerous hurricane.  It is capable of causing widespread extensive damage.  There are likely to be widespread power outages.  Irma will also generate a storm surge of 15 feet (5 meters) in some locations.  Irma will drop locally heavy rain and flooding could occur in some places.