Tag Archives: Arkansas

Tropical Storm Harvey Moves Into Louisiana, Irma Strengthens Quickly

Tropical Storm Harvey finally moved into Louisiana on Wednesday after lingering for several days over the northwestern Gulf of Mexico.  Harvey weakened to a tropical depression after it moved inland.  At the same time a new tropical storm named Irma strengthened quickly over the eastern Atlantic Ocean.  At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Harvey was located at latitude 31.7°N and longitude 92.3°W which put it about 30 miles (50 km) north-northeast of Alexandria, Louisiana.  Harvey was moving toward the north-northeast at 9 m.p.h. (15 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 998 mb.

After dropping record rainfall and causing destructive floods of parts of southeastern Texas and western Louisiana, Tropical Depression Harvey finally started to move steadily toward the north-northeast on Wednesday.  Harvey was still producing heavy rain over parts of western Louisiana, but the fact that it was moving should limit the total rainfall at any location.  Bands of showers and thunderstorms on the far eastern periphery of Harvey’s circulation were also dropping heavy rain.  Some of those thunderstorms were strong enough to approach severe criteria.  Tropical Depression Harvey is forecast to move toward the Ohio River Valley during the next several days and it will bring windy, wet weather to the Middle Mississippi and Ohio River Valleys.  Rain associated with the circulation of Tropical Depression Harvey could also reach the Mid-Atlantic States later this week.

At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Irma was located at latitude 16.4°N and longitude 32.2°W which put it about 545 miles (875 km) west of the Cabo Verde Islands.  Irma was moving toward the west at 12 m.p.h. (19 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 999 mb.

The circulation of Tropical Storm Irma organized quickly on Wednesday.  Numerous bands of showers and thunderstorms formed and began to revolve around a well organized center of circulation.  Thunderstorms in the core of Irma generated well developed upper level divergence which pumped away mass in all direction.  There were occasional satellite images which hinted that an eye could be forming at the center of Tropical Storm Irma.

Tropical Storm Irma will be moving through an environment that will be favorable for intensification.  Irma will move over water where the Sea Surface Temperature is near 28°C.  The upper level winds are weak and there is little vertical wind shear.  Irma is likely to become a hurricane on Thursday and it could intensify rapidly if an eye forms.  Tropical Storm Irma is forecast to become a major hurricane and it could become one of the big classic Cape Verde hurricanes.

A strong subtropical high to the north of Irma is steering the tropical storm toward the west and a general westerly motion is forecast to continue for the next few days.  There is more divergence in the model guidance after a few days and the future track of Irma when it nears the Lesser Antilles is more uncertain.  Tropical Storm Irma has the potential to become a big dangerous hurricane and it will need to be watched carefully.

Tropical Storm Harvey’s Record Rains Continue Over Texas and Louisiana

The record setting rainfall from Tropical Storm Harvey continued over southeastern Texas and Louisiana on Tuesday morning.  A rain gauge southeast of Houston near Mary’s Creek at Winding Road has measured 49.20 inches (125 cm) of rain from Tropical Storm Harvey as of 9:00 a.m. CDT on Tuesday.  This total sets a new record for the most rainfall from a tropical cyclone over the contiguous 48 states of the U.S.  The previous record was 48 inches (122 cm) dropped by Tropical Cyclone Amelia in 1978 over Medina, Texas.

At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Harvey was located at latitude 28.4°N and longitude 94.3°W which put it about 115 miles (185 km) south-southwest of Cameron, Louisiana.  Harvey was moving toward the north-northeast at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 997 mb.

A Tropical Storm Warning is in effect for the portion of the coast from Port O’Connor, Texas to Morgan City, Louisiana.  A Tropical Storm Watch is in effect for the portion of the coast from Morgan City to Grand Isle, Louisiana.

The center of Tropical Storm Harvey moved back over the Gulf of Mexico late on Monday and it is currently over the northwestern Gulf.  Harvey is still producing heavy rain over southeastern Texas and parts of Louisiana.  There is still a well defined center and strong counterclockwise rotation in the lower levels of the atmosphere.  Dry air wrapped around the circulation of Harvey and there are mainly lighter showers near the center of the tropical storm.  There are several stronger bands of thunderstorms on the eastern periphery of the circulation.  Those bands are dropping heavier rain over eastern Louisiana and parts of Mississippi.  The strong counterclockwise rotation is transporting moist air over land.  Increased friction over the land is causing more convergence which is pushing the air upwards.  Stronger rising motion is generating areas of heavier rain over southeast Texas and southern Louisiana.  In addition, the land is warming during the day, which is making the lower atmosphere more unstable and contributing to the heaver rain.

Flood Watches and Warnings are in effect from Northwest Florida to Southeast Texas because of the potential for more heavy rain.  Tropical Storm Harvey is finally starting to move slowly toward the north-northeast.  It should make a landfall on the coast of Louisiana early on Wednesday.  Tropical Storm Harvey will weaken as it moves farther inland and it should move over the Lower Mississippi River Valley as a tropical depression late this week.  The rain over southeastern Texas and southern Louisiana should end once Harvey moves farther inland.

Elsewhere, a low pressure system designated Potential Tropical Cyclone Ten was bringing gusty winds and higher waves to portions of the Mid-Atlantic coast.  At 11:00 a.m. EDT on Tuesday the center of Potential Tropical Cyclone Ten was located at latitude 34.4°N and longitude 77.2°W which put it about 35 miles (60 km) west-southwest of Cape Lookout, North Carolina.  It was moving toward the northeast at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1006 mb.  A Tropical Storm Warning was in effect from Cape Lookout to Duck, North Carolina including Pamlico and Albemarle Sounds.  Potential Tropical Cyclone Ten is forecast to merge with a front and become a strong extratropical cyclone over the western Atlantic Ocean.

Slow Moving Tropical Storm Harvey Causing Record Flooding in Texas

Slow moving Tropical Storm Harvey was causing record flooding in Houston and other places in southeast Texas.  At 2:00 p.m. EDT on Sunday the center of Tropical Storm Harvey was located at latitude 29.0°N and longitude 97.2°W which put it about 25 miles (40 km) northwest of Victoria, Texas.  Harvey was moving toward the southeast at 2 m.p.h. (3 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 1000 mb.

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

The center of Tropical Storm Harvey is drifting back toward the Gulf of Mexico.  A significant portion of the eastern side of Harvey is over water and the strongest winds are occurring in rainbands over the Gulf of Mexico.  Those winds are the reason Harvey is still a tropical storm and why there is still a tropical storm warning for a portion of the coast.  The circulation around Harvey is circulating over the water and it is transporting large amounts of moisture over southeast Texas.  Strong convergence into the center of Harvey is lifting the air and it is producing prolonged periods of heavy rain when rainbands move inland.

The extremely heavy rain in Harvey is causing record flooding in parts of Houston and other locations in southeastern Texas.  The Buffalo Bayou is currently at 67.46 feet (20.56 m).  The previous record water level was 61.2 feet (18.65 m).

The slow movement of Tropical Storm Harvey is exacerbating the flooding.  The winds are the steering level are weak and Harvey is now drifting back toward the southeast.  Harvey is drifting back over places it moved over on Saturday.  The center of Tropical Storm Harvey could drift back over the Gulf of Mexico.  If the center of Harvey moves back out over water, it would likely maintain its intensity.  Tropical Storm Harvey is forecast to continue to drop heavy rain over southeastern Texas and southwestern Louisiana during the next several days.

Harvey Weakens to Tropical Storm, Still Dropping Heavy Rain on Texas

Hurricane Harvey weakened to a tropical storm on Saturday afternoon, but it was still dropping heavy rain on parts of Texas.  At 2:00 p.m. EDT on Saturday the center of Tropical Storm Harvey was located at latitude 29.1°N and longitude 97.6°W which put it about 45 miles (75 km) west-northwest of Victoria, Texas.  Harvey was moving toward the north-northwest at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 987 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Baffin Bay to High Island, Texas.

The core of Hurricane Harvey moved inland over San Jose Island on Friday night.  It passed over Rockport, Texas and moved slowly north-northwest on Saturday.  The strongest wind occurred near Port Aransas, Rockport and Ingleside.  Some of the peak wind gusts were:

Port Aransas          132 m.p.h.   (213 km/h)

Copano Village       125 m.p.h.  (202 km/h)

Lamar                      110 m.p.h.  (177 km/h)

Rockport                 108 m.p.h.  (174 km/h)

Taft                            90 m.p.h.  (154 km/h)

Other than the fact that it is over land, Tropical Storm Harvey is in an environment favorable for a tropical cyclone.  The upper level winds are weak and there is little vertical wind shear.  Tropical Storm Harvey has weakened during the day, but it has maintained a very symmetrical structure.  Steady rain is falling in the core of the circulation and several bands of showers and thunderstorms in the outer portions of the circulation.  Tropical Storm Harvey has already produced heavy rain in some locations.  Some current rainfall totals are:

Aushell                   15.10″       (38 cm)

Coleto Creek         12.57″       (32 cm)

Richmond                9.60″       (24 cm)

Edna                       10.06″       (25 cm)

Danbury                  7.89″        (20 cm)

Sugarland               7.56″        (19 cm)

The steering winds are weak and Tropical Storm Harvey is forecast to make a slow counterclockwise loop during the next several days.  Since Harvey will not move very much, it will continue to rain in many of the same locations.  The potential for flooding will increase as the rain continues to fall.  Some rivers and streams could experience record flood levels.

Tropical Depression Cindy Brings Stormy Weather to Southern U.S.

Tropical Depression Cindy brought stormy weather to parts of the southern U.S. on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Depression Cindy was located at latitude 33.1°N and 93.5°W which put it about 70 miles (115 km) southwest of Little Rock, Arkansas.  Cindy was moving toward the north-northeast at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 20 m.p.h. (30 km/h) and there were wind gusts to 30 m.p.h. (50 km/h).  The minimum surface pressure was 1000 mb.

Tropical Storm Cindy made landfall early on Thursday morning near the border between Texas and Louisiana.  Cindy moved steadily northward during the day and it was centered over southwestern Arkansas by Thursday night.  Broad counterclockwise rotation around Cindy transported warm and very humid air over the southern U.S.  Bands of showers and thunderstorms dropped locally heavy rain in some places.  Rivers and streams were above flood stage in several southern states.  Flash Flood Warnings and Flash Flood Watches were issued for portions of the southern U.S. and Ohio River Valley.  Several tornadoes formed in the bands of thunderstorms.  A tornado in Alabama caused property damage.  Southerly winds blowing toward the shore were still causing storm surges along the northern coast of the Gulf of Mexico.

Tropical Depression Cindy is forecast to move northeast toward the Ohio River Valley on Friday.  It will continue to produce locally heavy rain.  A slow moving cold front will approach the region from the west.  A band of stronger convergence could develop where the counterclockwise flow around Cindy interacts with the flow along the cold front.  Higher rainfall totals may occur where this interaction happens.  Wind shear created by the interacting weather systems could also create the potential for some tornadoes.  Tropical Depression Cindy could merge with the cold front during Friday night or Saturday.

Tropical Depression Bill Bringing Rain to Arkansas and Missouri

Tropical Depression Bill continued its slow movement over the South Central U.S. on Thursday and it brought rain to Arkansas and southern Missouri.  At 11:00 p.m. EDT on Thursday the center of Tropical Depression Bill was located at latitude 35.9°N and longitude 93.8°W which put it about 20 miles (30 km) east of Fayetteville, Arkansas.  Bill was moving toward the east-northeast at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 20 m.p.h. (30 km/h) and the minimum surface pressure was 1005 mb.

Even thought the center of Bill has been over land for more than 48 hours, it retains many of the characteristics of a tropical cyclone.  It has a well defined cyclonic circulation with a warm core in the middle troposphere and there is upper level divergence.  As a result, Bill is still officially classified as a tropical depression.

Bill is moving around the western end of a high pressure system centered over the Atlantic Ocean.  It should continue to move toward the east-northeast during the next several days.  On its anticipated track Bill will bring rain to northern Arkansas and southern Missouri on Friday.  It will move up the Ohio River Valley on Saturday and enhance the rainfall in those areas.  The circulation of the tropical depression could merge with a nearly stationary frontal boundary north of the Ohio River during the weekend.  Heavy rain falling on saturated ground could create the potential for flooding in some areas.

Tropical Depression Bill Crossing Red River Into Oklahoma

Tropical Depression Bill moved northward across north Texas on Wednesday and brought heavy rain to parts of Texas and Oklahoma.  At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Bill was located at latitude 33.7°N and longitude 97.3°W which put it about 65 miles (105 km) north-northwest of Dallas, Texas.  Bill was moving toward the north at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h).  There were wind gusts to 50 m.p.h. (80 km/h) in some thunderstorms.  The minimum surface pressure was 999 mb.

Bill still has a well organized circulation at the surface and throughout the troposphere.  There is still a warm core in the middle troposphere and divergence in the upper levels.  The upper level divergence pumped out the same amount of mass as converged in the lower levels and the surface pressure remained constant on Wednesday.  Some drier air is wrapping around the southern part of the circulation and most of the rain is falling north and east of the center.  The slow movement of Bill has generated significant amounts of rain and flooding is occurring in some parts of Texas and Oklahoma.  A few thunderstorms have also produced damaging wind gusts.

Bill is expected to turn toward the northeast as is moves around the western end of a high pressure system centered off the southeast coast of the U.S.  It will move slowly across Oklahoma on Thursday and across Arkansas on Friday before moving up the Ohio River Valley during the weekend.