Dick Faurot's Weather Blog: Turn Around, Don't Drown
Turn Around, Don't Drown; you'll probably be hearing that a lot tonight, and Thursday and perhaps for several days after that.
As mentioned yesterday, the remnants of TS Bill are moving into OK as I write this and as you can see on the rainfall map for today, courtesy of the OK Mesonet, Bill has already dumped too much rain too fast for the far southern counties. Often, the heaviest rains with tropical systems occur during the overnight hours and that may be the case with Bill as we go through the night tonight. But, due to its slow movement there will be heavy rains into the day Thursday as well before it all comes to an end by early Friday.
As was also mentioned yesterday, movement of these type systems can be very erratic, as they are typically embedded in a weak wind flow pattern aloft, and Bill will be no exception. So far today, the remnant circulation seems to have slowed considerably along the Red River south of OKC. But, all indications are that it will take a bit of a right turn as it begins moving to the NE over the next 24-48 hours.
The exact track will have a tremendous impact on how much rain falls and how fast at any given location as there will be a very tight gradient on the W side of the system. Some locations may only receive an inch or less while other locations just a few miles further east and closer to the circulation center may end up with 10” or more. Yep, would not be surprised if some isolated reports come in with as much as a foot of rainfall by the time it is all said and done.
Notice the 3-day QPF map for example and you can see that very tight W-E rainfall gradient. Obviously, any subtle deviations in the movement of the system will result in major changes in the amounts. Also, keep in mind that even if your particular location does not get the really high rainfall totals, only an inch or two of rain in a very short time will still cause significant flooding issues and the rainfall rate will also be a problem.
Not only that, but very weak tornadoes will also be possible. We commonly call them a landspout, as opposed to a waterspout tornado, as they are very small, very weak and very short-lived. Even so, if one happens to occur at your location, they can still cause a lot of damages. But, since there is no circulation aloft associated with these, they are nearly impossible to provide any advance warning for.
Right now, the projected track will be parallel to the I-44 corridor, possibly right along the corridor itself but more likely further to the SE. At any rate, it will be along and to the right of that track that the heaviest rains will most likely occur. Landspouts could occur most anywhere though.
As that circulation moves to the NE, there will also be some gusty winds associated with it as our winds go from E/SE to E and eventually N as it moves on past your location. Although the winds will, for a time, shift to the north on the back side of the circulation, it will take a while before the rains come to an end; as mentioned some lingering showers will be possible into the morning hours of Friday for the more eastern counties.
After that, lots of sunshine should prevail through the weekend and into next week as ridging aloft builds over the state, resulting in very warm, humid conditions with heat index values likely near 100 each day.
As you can see on our forecast page, our rain chances for the weekend and into next week are in the slim to none category. Not only that, but the 6-10-day outlook also suggests a drier pattern along with above normal temperatures so hopefully we will get some badly needed relief during that time frame.
So, stay tuned and check back for updates.