Severe Storms Possible for OK/TX

** Severe Storms Possible Through Wednesday, Greatest Threat Tuesday Overnight **

Forecast by Greg Whitworth/ Fox 25 TV

I have bumped some highs well into the 80s to account for rapid warming seen this morning.Thunderstorms will occur across southwest and south central Oklahoma today. Some pulse severe storms could produce low end severe weather on the order of small hail and gusty winds. An upper level storm system developing across northern Mexico will send waves of energy to the northeast over the next few days. One wave approaches around noon today, a second one around 1 a.m., and another around 7 pm Tuesday. The main vort max piece of energy comes out overnight Tuesday and lasts through Wednesday across the eastern part of the state. On the surface, south winds continue through early Wednesday. Severe weather will likely develop along a weak dryline/trough across the northwest Texas panhandle and western Kansas, were severe storms have already formed this morning. The activity across Kansas is moving east southeast and should affect areas from Wichita north. Storms that form across the panhandles later today could roll across the state tonight, and low end severe weather is possible overnight. Models indicate a warm front will move northward, forming just south of the Red River tonight and lifting north to northern OK by afternoon. I suspect the warm front will pass OKC around 1 pm and this is noted in MOS dew point trends.On Tuesday, the dryline stays across the central and western TX panhandles down toward Lubbock. The Tuesday wave should set off a round of severe weather across the Texas south high plains that should roll northeast towards Oklahoma. CAPE in the eastern half of the TX panhandle is forecast to be up to around 2,000 by the NAM. These storms roll across Oklahoma Tuesday night as a squall line with high winds and hail. The convection appears to be crossing central and western Oklahoma during the heating hours, so I have dropped high temperatures on Wednesday by several degrees to account for this.On Wednesday, the situation is uncertain. GFS showed the dryline is expected to make a surge east and pass Oklahoma City by 4 p.m. with a cold front trailing behind by a few hours. It is difficult to tell if we will have another round of severe storms Wednesday afternoon or not. A lot of it depends on how fast round #1 moves out. If we do not recover and destabilize, Wednesday could turn into an eastern Oklahoma event. However, typically the models move the precip along too slow, and if that turns out to be the case, highs for Wednesday would need to be bumped back up. NAM is suffering from the double-low problem again with the dryline remaining entirely in Texas. Since we have seen this solution not pan out before, it will be discarded in favor of the GFS. GFS indicates the triple point to be somewhere across northwest Oklahoma.There is not a lot of cool air behind this system. The GFS wants to keep dewpoints high behind the system, which I believe is bogus. I have discarded the 0Z MOS which had lows in the mid-50s after the frontal passage. Winds and cloud cover should leave Thursday morning in the mid 50s, but temperatures should drop off Friday morning back into the 40s and 50s across the state. On Saturday, 0Z GFS threw in a new front arriving around 7 a.m. with another weak front trailing right behind it. Then, the stronger front which has been in the models for many days now, arrives around 1 a.m. in OKC. GFS has pushed the weak longwave trough up 6 hours with it now arriving at 1 a.m. coincident with the front. I have left pops at 40% to account for this run-to-run consistency which has been present since near the end of the 12 day forecast period. The only reason I didn't bump it higher was the aforementioned morning front and possible timing issues if the system slows down any more, which would then push it into Sunday.Right now Mother's day looks quiet with highs in the low 70s, light winds, and plenty of sun.The next storm system beyond the 7 day looks to arrive Tuesday and Wednesday of the following week. Right now this one looks quite dynamic, with difluent flow aloft on Tuesday, strong south winds and a dryline near US highway 81. GFS forecasts the dryline to retreat west to the OK border Tuesday night, then make another run east on Wednesday, passing OKC around 4 p.m. with a cold front trailing right behind. A significant upper level vort max is seen crossing the area at the same time so it appears ripe for severe weather. This trend has also shown up in a couple of days of runs and is becoming more likely. Expect a couple of days of north winds behind the system with plenty of clouds to wrap up days 11 and 12 (Thursday and Friday of next week).OKC 84 63/82 65/75 56/73 50/76 59/78 56/72 50/79 61/84 66/84 54/73 47/66POPs Monday 40%, Monday night 50%, Tuesday 50%, Wednesday 80%, Saturday 40%, following Tuesday 30%, Wednesday 40%, Thursday 10%.Breezy Monday, Windy Tuesday and Wednesday, Breezy Saturday, Breezy the following Monday, Windy Tuesday, Windy Wednesday.

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Greg