Tropical Storm Karen Update – 11 PM Forecast Discussion/Impacts
October 4, 2013 Leave a comment
Here’s the latest advisory coming from the National Hurricane Center this evening. The forecast track remains largely unchanged from previous forecasts; a turn to the northeast is expected over the next 24 hours, but this turn could be delayed a little longer than currently forecast given that Karen stalled earlier this evening. Nonetheless, the center of circulation will pass well to our south.
It should be mentioned that Karen continues to fight very hostile conditions in the central Gulf, most notably the vast amounts of dry air to its northwest and west. It’s possible that Karen may not recover in this environment and it continues a gradual weakening trend towards its landfall. We’ll be watching it closely.
Saturday: Tomorrow should feature a mixture of clouds and sunshine with temperatures rising into the mid 80s. The good news…Alabama’s game against Georgia State tomorrow morning will be rain-free, maybe an isolated storm is possible by the 4th quarter.
Saturday Evening: The strong trough of low pressure will continue eastward across the nation’s midsection. Ahead of this, a southeasterly flow will prevail across our area tomorrow, helping keep moisture in our area. Karen should be close to making landfall somewhere near the far southeastern shores of Louisiana followed by a second landfall near Pensacola as it gets absorbed by the approaching trough.
Rain should increase from southwest to northeast overnight Saturday into Sunday morning as tropical moisture from Karen interacts with the approaching cold front from the west. This continues to be a messy situation, as exact placement of the heaviest axis of rain is still difficult to determine. For now, I think it’s best to not stray too much from our previous forecast thinking, which follows below…
For west-central Alabama including Tuscaloosa – rain increases after midnight Saturday lasting through Sunday. Rain amounts, on average, should range from 1/2″ to locally 2″ in spots. The heavier rains should be over south-central Alabama where the better tropical moisture will reside. Winds should not be much of a problem up this way, a few gusts up to potentially 20-30 mph could be found especially in the vicinity of highway 80. Lastly, any tornado threat should be confined to our southeast where the better low-level shear will be in place.
As a cold front moves from west to east Sunday afternoon, another increase in showers and perhaps a couple of thunderstorms is possible before we can mark the end of rain chances late Sunday evening through Monday morning. The Storm Prediction Center maintains a low-end probability of an isolated severe storm with this activity, but widespread cloud cover will likely inhibit appreciable destabilization needed for organized storms. Still, the dynamic lift associated with this feature should be sufficient enough to set off a skinny line of showers and storms by Sunday afternoon.
The clearing may be slow, however, as a very strong bowling ball-type area of mid/upper level low pressure pinwheels to our north. Residual uplift with one last spoke of energy may squeeze out a shower/cloud cover Monday morning, but dry air quickly takes over and we’ll see the return of maximum sunshine by Monday afternoon through most of the upcoming work week.