Morning Storms

Showers and storms formed last night across the northern part of the state and have been moving from the northwest to the southeast this morning into our area.  A few of these showers and storms have produced some hail, but most of the storms have been below severe levels.  The surface boundary is still south but the front at 5000 ft. is located very close to northeastern OK.  This front at the 850mb level of the atmosphere is providing some convergence for storms to propagate this morning across the area.  The NSSL 4K model did an excellent job in pinpointing this activity yesterday afternoon.  The 18NAM also indicated a good signal for these early morning showers.   

RAW NAM data is suggesting temperatures a little cooler for extreme northern OK than our currently advertised 67 for this afternoon.  Some locations across northern OK and southern Kansas could remain in the upper 50s this afternoon if point sounding data is to be believed as the gospel of weather forecasting for today.  I have my doubts and will keep our current numbers in the lower to mid-60s for afternoon highs, even in extreme northern Ok and southern Kansas,  along with East winds for the majority of the day.  Mid 60s will "feel cooler" compared to the 70s of previous days and the jacket may not be a bad idea for the kids at the bus stop this morning.

We continue to see signs in the pattern for severe storms in the extended forecast.  The day to day model data will no doubt change, but I feel confident that several rounds of severe storms will be likely by Friday into the weekend.   

The upper air flow will be from the southwest soon as a major upper level trough begins to move closer to our area.  Southeast to south surface winds will return as the weak boundary currently south of our area moves northward or reforms later tonight to our north.  This will place all of the southern plains, and possibly most of the central plains in the classic warm sector of this developing mid latitude cyclone.  Winds aloft will be gradually turning with height and also increasing speeds with height in the atmosphere.  This deep layer shear is a key ingredient in severe storm formation and allows thunderstorm updrafts to rotate and become tilted in the axis layer.  This tilt in the updraft allows unobstructed inflow of rich low level moisture into the storms which can keep allow the storms to last for much longer periods of time compared to non-rotating thunderstorms.  Rotating thunderstorms don't always mean tornadoes, but usually always mean the potential for hail.  In the expected dynamics and pattern for Thursday through the weekend, the parameters would suggest both tornadoes and hail as a concern.   

We've been discussing this "pattern" for about a week now but the specifics of the system are frankly yet to be known with any supporting data.  But the pattern recognition alone has given us ample to confidence to suggest a severe weather potential for a few days beginning Thursday across western Ok and continuing across the rest of the state from Friday into the weekend.   It appears the higher chance period for most of Eastern OK will be Saturday or Sunday.

The EURO continues to offer a solution of closing off the H5 low which would slow the system down allowing for rain to continue into Monday.  If this is the case, Sunday evening into Monday midday some flooding issues may be a concern for a few locations across extreme eastern or southeastern OK.