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The National Hurricane Center is monitoring an area of disturbed weather over the eastern Yucatan Peninsula this evening. Various weather models have been hinting at the possibility of this system becoming a weak tropical cyclone for a few days now. Let me start off by saying that an upper level low located over South Texas is going to keep this system east of Texas. Should this system develop it will be a threat to the northern Gulf Coast between Mississippi and the Florida Panhandle.

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This evening’s tropical weather model tracks are in fairly decent agreement about a track to the north/northeast over the next few days. Invest 99 should move into the southern Gulf of Mexico early on Sunday. This evening’s water vapor imagery does not show anything particularly organized. A flareup of convective activity is noted off the eastern coast of the Yucatan but overall just a broad area of disorganized activity. Regardless of tropical cyclone development the low pressure system should make progress to the north on Sunday. With an upper level low located over the Texas coast the steering currents should cause Invest 99 to make a turn to the north/northeast Sunday Night into Monday. The system should continue a north/northeast track on Monday and be near the northern Gulf Coast by Monday Night into the morning hours on Tuesday.

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Tropical weather models are not aggressive with the development of Invest 99. While sea surface temperatures are certainly quite warm over the Gulf the upper low over the Texas coast is creating some wind shear over the Gulf. Tropical cyclones thrive on low-wind shear environments so conditions will only be marginally conducive for development. If Invest 99 is able to become a tropical cyclone we’re looking at it being a tropical depression or perhaps a weak tropical storm. By far the biggest impacts will be from heavy rain.

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Moisture from Invest 99 in combination with the upper level low located on the Texas Coast will enhance precipitation chances on the Southeast Texas coast over the coming days. The Weather Prediction Center rainfall forecast through Thursday shows the potential track of Invest 99 in the Southeast United States. Besides the Texas coast it’s looking like a fairly dry week for most of Texas as an upper level high pressure builds in.

The following is the full tropical weather outlook text from the National Hurricane Center for Invest 99.
An area of low pressure located over the eastern Yucatan Peninsula
is producing disorganized showers and thunderstorms and gusty winds
over portions of the northwestern Caribbean Sea, the southeastern
Gulf of Mexico, and the Yucatan Peninsula. This system is expected
to move northward at about 10 mph into the southern Gulf of Mexico
on Sunday and should then move more quickly northward or
northeastward as it interacts with an upper-level low near the
Texas coast. While upper-level winds are only expected to be
marginally conducive, there is some potential for this system to
become a tropical cyclone during the next couple of days before it
reaches the northern Gulf Coast. Regardless of tropical cyclone
formation, this disturbance is likely to produce locally heavy
rainfall over portions of the northern Gulf Coast and southeastern
United States early next week. An Air Force Reserve reconnaissance
aircraft is scheduled to investigate this system tomorrow, if
necessary. For additional information on this system, see High Seas
Forecasts issued by the National Weather Service and products from
your local National Weather Service office.
* Formation chance through 48 hours…medium…40 percent
* Formation chance through 5 days…medium…40 percent