BETTER AGREEMENT: There's still some uncertainty around Isaac; it's final destination remains unclear. But, we feel like we now have enough data to make some baseline predictions for Alabama. Please note that these predictions are based on the current NHC track. If that track shifts significantly, we'll have to adjust our forecast accordingly.
If, however, Isaac's track only shifts slightly, the weather conditions here won't be affected much.
Isaac is a very large storm and will bring us periods of heavy rain, some gusty wind and isolated, spin-up tornadoes.
Here are some maps, these should answer all of your "what will happen where I live" questions...first, a look at the wind issues for Alabama. If the current track verifies, the worst wind would stay west of Alabama and most of us would have a stiff breeze but nothing damaging or dangerous:
What about rain? It won't rain all day, but we expect feeder bands to bring us intermittent periods of heavy tropical downpours beginning Tuesday and lingering through Thursday. Heavy rain is likely in southwest Alabama:
Frankly, the greatest risk from Isaac in central and south Alabama will likely come from spin-up tornadoes. Hurricanes are large areas of low pressure that create significant wind shear and vorticity in the atmosphere. That shear interacts with storms in a tropical airmass to create rotation and brief tornadoes.
ALL of our part of Alabama faces the risk of isolated tornadoes. Here's the map:
The SPC has placed us under their standard "Slight Risk" of severe weather, and it's quite likely that we'll see tornado watches in effect for parts of Alabama Tuesday, Wednesday and perhaps even Thursday. Some areas could stay under watches for 24 hours or more. We'll have our weather office staffed around the clock and will provide team coverage of Isaac as it approaches the northern Gulf coast.
TIMELINE: Rain/wind from outer bands could arrive in south Alabama as early as tomorrow morning. The weather Tuesday will slowly go downhill. Rain and wind will begin to increase Tuesday night and Wednesday as the storm approaches the Louisiana coast. The outer bands will roll across Alabama from the east, bringing gusty wind, heavy rain and a few isolated tornadoes.
Those bands will continue to sweep across our state as Isaac slowly moves into Mississippi on Thursday - isolated tornadoes will remain likely.
By Friday, the weather should begin to slowly improve.
STAY INFORMED: Isaac may still hold more surprises; it's imperative that you keep yourself informed in the days ahead. Our hurricane tracker at WSFA.com is first-rate, I encourage you to check it out. Our iPhone, iPad and Droid apps can keep you updated well, too. They are free, you simply have to go to your App Store or Droid Market and search "WSFA Weather."
You can also get constant updates and post questions/pictures/reports on Facebook - in fact, we're posting each NHC update to Facebook as they come out:
And, last but not least, we publish tons of great weather content over on Twitter - we invite you there, too:
-Josh Johnson, Doppler 12 StormVision Meteorologist