UPDATE: 5:30 p.m. Thu 30 August 2012
"Isaac" is now moving almost due north; scattered showers and a few thunderstorms are possible as it moves through Arkansas, but amounts will be spotty and no flooding is expected. The NHC track map shows this below:
I expect few if any areas to receive even an inch of rain. It will be very hot for the Labor Day weekend with highs around 100. This will be the last post on Isaac.
UPDATE: 6:30 p.m. Wed 29 August 2012
The forecast remains about the same as posted below; I expect mostly cloudy, windy conditions for most areas late Thursday into Friday. The potential for significant rainfall is along and east of Highway 75, but spiral rain bands associated with the remnants of Isaac can extend far from the center, so a few showers are still possible as far west as Ardmore and Gainesville.
“Isaac” is hogging weather news along the Gulf Coast, and there’s reason right here in Texoma to keep a close eye on it.
The steering currents aloft suggest the core of the storm should track along the Arkansas-Oklahoma border Thursday-Friday as it moves northward.
Tropical cyclones tend to produce very heavy rain around their core at night as they decay, with a larger area of scattered spiral rain bands during the day.
Expect the rain pattern to be generally underneath and to the east of the center.
The most likely track will put the eastern half of Texoma, generally from Ada to Sherman and eastward, in the zone for potential rainfall Thursday night and Friday. If the system moves as I expect, there will be a very sharp drop off in rain the furthest west you go in our area.
This crazy-looking map shows the computer output for about two dozen models:
a fair number of them now bring Isaac close enough to produce rain for at least
the eastern parts of Texoma. This matches up well with what the steering currents
are doing as well.
What about wind? The damaging winds will be long gone by the time Isaac gets here, but it could be very blustery with winds of 30 to 40 late Thursday and into Friday. There’s also the risk of isolated tornadoes with any decaying tropical system, as seen in 2010 over Dallas with Tropical Storm “Hermine”.
Even a 50 mile change in the expected track could make the difference between no rain for Texoma at all and a real soaker for some parts. The window for Isaac to bring storms is late Thursday and most of Friday. Stay tuned.