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Tropical Storm Alex's Yucatan Landfall

By: Dr. Jeff Masters, 8:52 AM GMT on June 27, 2010

Update: Here's the 500AM EDT radar image from Belize. Alex's eye is roughly 150 km NW of the radar.

This Animated loop shows the development of Alex's eye. The page for Belize's radar is here.

The 500AM EDT forecast is a bit different than the previous forecast. Essentially, it looks like the area of high pressure in the northern Gulf of Mexico will weaken due to a trough over the eastern US. This will weaken the steering currents and slow's Alex's motion over the Gulf of Mexico. The reduced storm motion will give Alex more time to intensify in a a warm SST/weak shear environment. The current forecast calls for Alex to become a category 2 storm before making landfall north of Tampico, MX late Wed. night/early Thursday morning.

The $64,000 question is "Will the ridge continue to weaken, allowing Alex to move north and continue intensification?" The 12Z global model runs will have more accurate forecasts than the the 6Z runs thanks to the presence of radiosonde data, so hopefully they'll provide an answer. It's still my opinion that Alex will not directly impact the oil spill recovery efforts, but I can't say that the chances of it doing so are getting smaller now.

This is Dr. Rob Carver, filling in for Jeff during the late shift. Tropical Storm Alex is currently moving over the Yucatan peninsula. Alex's intensity has dropped to 50 knots in the latest advisory with further weakening expected as the storm moves over land. After Alex moves into the Gulf of Mexico, intensification is expected because of warm sea-surface temperatures and weak vertical wind shear. An area of high pressure in the northern Gulf of Mexico will guide Alex into a WNW-NW track. The 200AM EDT forecast calls for Alex to intensify into a category 1 hurricane before making landfall just north of Tampico, MX.

In my judgement, the chances of Alex moving northwards and directly interfering with the Deepwater Horizon oil spill recovery efforts are small and getting smaller with time. I agree with Jeff's assessment that Alex will generate 2+ foot swells that would interfere with skimming operations

Currently, the main threat from Alex is flooding due to heavy rains. NHC is forecasting rainfall amounts from 4 to 8 inches with higher amounts over mountainous terrain, causing flooding and possibly mudslides.

Fig. 1Forecast of 24-hour accumulated precipitation from TS Alex.

Alex's Belizean Landfall
Jeff saved this radar image of Alex making landfall.

Fig. 2Base reflectivity at 2315Z 26 June 2010 at Philip Goldson Airport

There isn't much storm structure apparent in the reflectivity data, just widespread areas of showers. Data from a nearby PWS shows that the peak windspeed was 43 mph. You can clearly see the circulation move past the station with changes in the wind direction and speed. You can also see when the rainbands passed over the station.

Invest 94L
Invest 94L is still out there, but it's not looking healthy. It's currently in an area unfavorable for tropical cyclogenesis and NHC thinks it has a 0% chance of becoming a tropical storm in the next two days. Current forecast models have 94L moving northwards and making a pass by Bermuda.

If things don't change significantly, Jeff is thinking about taking Sunday off. However, rest assured that if Alex starts charging towards the US, Jeff or I will put up a new entry. In any event, I'm planning on posting an update sometime late Sunday evening.


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