Very Warm Start to the Week, Much Cooler by the Weekend.

Sunday, October 21st 2012, 9:16 pm
By: News On 6

In this morning's blog, I pointed out how much warmer we were to start the day compared to Saturday morning. Turns out that we tied a record morning low here in Tulsa and as the map on the right shows, that warm morning start also produced a very warm afternoon. No records this afternoon, but notice much of W OK was well into the 90s.

The mostly cloudy skies on this side of the state helped keep temperatures somewhat in check this afternoon and we expect mostly cloudy skies to start the day on Monday as well. Together with a brisk southerly wind overnight, overnight lows will likely set records again on Monday morning. As the day wears on, a weakening disturbance aloft will be passing over the state and will provide at least a chance of showers/storms. Although we have abundant low level moisture with dew point temperatures running in the upper 60s and the precipitable water values are running about twice what is normal for this time of year, there is the problem of a layer of warm air aloft that will be difficult to overcome.

The very warm air aloft forms what we refer to as a capping inversion which effectively acts like a lid on vertical development. However, if something can penetrate the inversion, there will be ample instability aloft for some decent storms to get going. More than likely though, any development will be elevated and not surface based but could still pose a wind/hail threat for Monday afternoon into the evening hours. The computer models are at odds regarding how to handle this inversion with the NAM basically dry and the GFS considered to be too wet. Given the uncertainty, have dropped the rain chances to 30% for Monday afternoon/evening/night.

After that, Tue and Wed will also be unseasonably warm along with gusty southerly winds and partly cloudy skies. The next cold front still looks to be on schedule later on Thursday and will be followed by much cooler conditions going into the coming weekend. There will be a chance of showers/storms with frontal passage later on Thursday, but right now it appears that the better chances will be on Friday. Some energy aloft will be moving overhead on Friday with cloudy skies, chances of rain and possibly even some thunder, gusty northerly winds, and temperatures likely staying in the 50s. In other words, Friday is shaping up to be a very raw day.

Some lingering clouds and maybe a few sprinkles into the day Saturday look to be followed by clearing skies that afternoon. That could set the stage for a freeze/frost either Sunday morning or Monday morning if not both. Daytime highs will likely stay in the 50s as well so potentially the coolest air of the season looks to be headed this way for the weekend.

In the meantime, stay tuned and check back for updates.

Dick Faurot