Tag Archive for: cyclone

Tropical Cyclone Threat Increases Later This Week

The National Hurricane Center and Harris County meteorologist Jeff Lindner now predict that a tropical cyclone will likely develop in the Gulf of Mexico later this week.

5-day outlook shows low pressure system tracking westward over warm Gulf waters.

Models Now Predict Westward Development

Overnight, the threat increased westward along the Louisiana and Texas coasts.

The National Weather Service expects a trough of low pressure located over central Georgia to move southward toward the northeastern Gulf of Mexico. There, it should form a broader area of low pressure in a couple of days. A tropical depression will likely form by the end of the week while the low meanders near the northern Gulf Coast.

Regardless of development, this system has the potential to produce heavy rainfall along portions of the northern and eastern U.S. Gulf Coast later this week. Formation chance in the next two days remains low at 10 percent, but increases to 80 percent in the 5-day outlook.

Likely Path

Upper air conditions appear favorable for a tropical system to form and then intensify over much of the US Gulf coast and northern Gulf. Models now predict that any Gulf system would tend to track more westward.

Intensity

“A tropical storm is likely and a hurricane is not out of the question,” says Lindner. “If forecast models continue to show the westward motion and potential threat to the northwest Gulf, significant forecast changes will be required over the next 24-48 hours.” 

What to Do Now

  • Closely monitor the progress of this system.
  • Check hurricane preparation kits and plans.
  • Be ready to enact those plans later this week.
  • Monitor weather forecasts closely.   

Posted by Bob Rehak on 7/8/2019

678 Days since Hurricane Harvey

Potential Tropical Cyclone #7 Headed into Gulf

At 2am EDT today, the National Hurricane Center (NHC) issued an update on a potential tropical cyclone headed toward Louisiana.  Maximum sustained winds at this time are 30mph. The NHC predicts the disturbance will become a tropical storm by tonight.

At this moment, it looks like the storm will make landfall east of the Houston area, putting us on the dry side of the storm. However, the NHC also warns that the forecast track could vary by more than 170 miles and that the width of the storm may exceed the cone of uncertainty shown below. This will increase our rainfall chances significantly later in the week.

Potential Tropical Cyclone 7 is headed toward Louisiana and Mississippi. If current forecasts are accurate, Texas will be on the dry side of the storm.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT

A Storm Surge Watch is in effect for the Mississippi-Alabama border westward to the Mouth of the Mississippi River

A Tropical Storm Watch is in effect reaching from the Alabama-Florida border westward to east of Morgan City, Louisiana, including Lake Pontchartrain and Lake Maurepas.

DISCUSSION AND OUTLOOK

The system is moving near 15 mph, and this general motion is expected to continue through Wednesday. On the forecast track, the disturbance will pass over the Florida Keys or the southern portion of the Florida peninsula today, move over the southeastern Gulf of
Mexico by this evening, and reach the central Gulf Coast by late Tuesday or Tuesday night.

Maximum sustained winds are near 30 mph with higher gusts. Gradual strengthening is forecast during the next 48 hours, and the disturbance is forecast to become a tropical storm by tonight.

  • Formation chance through 48 hours is high at 80 percent.
  • Formation chance through 5 days remains high at 80 percent.
  • The estimated minimum central pressure is 1012 mb (29.89 inches).

HAZARDS AFFECTING LAND

STORM SURGE:

The combination of a dangerous storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide…

  • Destin Florida to the Mississippi-Alabama border…1 to 2 ft.
  • Mississippi-Alabama border to the Mouth of Mississippi River…2 to
    4 ft.
  • Mouth of the Mississippi River to the Louisiana-Texas border…1 to
    2 ft.

The deepest water will occur along the immediate coast near and to the east of the landfall location, where the surge will be accompanied by large waves. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.

RAINFALL:

The disturbance is expected to produce heavy rainfall along the central Gulf Coast by the middle of the week.

WIND:

Tropical storm conditions are possible within the watch area by late Tuesday.  Winds should reach 40mph by 9/4 and 50 mph by 9/5. Maximum winds inland should reach 30 knots with gusts to 40.

EXTENDED OUTLOOK:

NOTE: Errors for track have averaged 150 nautical miles (NM) on day 4, 175 NM on day 5, and near 15 KT each day for intensity. So stay alert and check forecasts several times each day. The current (unrelated) low pressure disturbance moving onshore is expected to bring widespread rainfall of 1 to 3 inches with 5 to 6 inches likely closer to the coast. If #7 stays on the current track, expect another 1 to 4 inches of rain. If it tracks more westward and slows down, we could see quite a bit more than that, according to Space City Weather. However, current forecasts predict rainfall toward the lower end of that spectrum.

LOCAL IMPACT FROM CURRENT STORM

As of 7pm Sunday night, Jeff Lindner, meteorologist for Harris County Flood Control predicted that the greatest impact from the current storm would be concentrated near the coast. He predicts street flooding is the largest threat. “Most creeks and bayous will be able to handle this amount of rainfall as long as it does not all fall in an hour or two. I think the biggest threats will be street flooding with hourly rates of 2-3 inches where any banding or training develops.”

Posted by Bob Rehak on 9/3/2018 @2:48 am.

370 Days since Hurricane Harvey