Tuesday Morning Update

Tuesday, May 29th 2012, 4:21 am
By: Alan Crone

We're in the middle of an active weather pattern for the state with the chance of showers and storms remaining through early Thursday morning.  The first part of this system arrived late yesterday evening into the pre-dawn hours with some much needed shower and thunderstorm activity.  Some of these storms were severe to our west bringing large hail and high winds to portions of central and southwestern OK.  Later today a few more storms will be possible, with a higher chance of storms arriving Wednesday evening into pre-dawn Thursday.   Some of the storms may be severe, including a moderate risk of severe storms for the Wednesday evening time period.

A weak boundary is lingering nearby this morning and may eventually waffle northward before stalling along the OK-Kansas state line or possible into southern Kansas.  Model data indicates the probability will remain for scattered storms this afternoon and evening along the boundary and also across far southeastern OK.  Any of the storms this afternoon and tonight may become severe with high winds and large hail the main threat.  Any storms near the boundary across northern OK could become super cellular with a tornado threat before storms would congeal into a small complex of storms moving east to southeast. 

A stout disturbance currently located across the Pacific Northwest will move closer to the central plains during the next 36 hours.  As this disturbance approaches the central plains, thunderstorms will form in Nebraska and/or southwestern Kansas Wednesday afternoon and rapidly become severe while moving east to southeast.  The pattern suggest ( and model data confirms) the likely hood of a complex of thunderstorms forming and moving across the area Wednesday evening through pre-dawn Thursday and severe weather will be expected in the form of damaging wind and large hail.  Discrete thunderstorms could produce tornadoes before congealing into a complex, but the higher likelihood for tornadoes would be early Wednesday afternoon across part of far Northwestern OK and southern Kansas. 

The timing of the Wednesday system remains tricky and will be refined during subsequent forecast cycles but current data suggests the window of opportunity will occur from Wednesday 6pm through 3am Thursday.  Latest NAM data is faster compared to previous runs and would bring the complex into northeastern OK around 6pm to 8pm.  Again, the timing of the system will be refined with additional incoming data later today.  The SPC (Storm Prediction Center) has posted a moderate risk for Wednesday's scenario and a slight risk for today and this evening for portions of the state.

The system will be moving away from the area Thursday morning with gusty northwest winds and drier air moving across the central plains into northern OK allowing for highs in the mid-70s.  Raw numerical data suggests the Friday morning lows may drop into the upper 40s for part of northern OK with highs in the lower 70s. 

The weekend at first glances appears in decent shape for most locations, but the pattern would suggest a chance of showers or storms across far northeastern OK and southeastern Kansas.  The EURO does support a slight chance Saturday morning, while the GFS would suggest a chance Sunday morning.  These chances would be on the low side and for only a small portion of the state.  I have elected to not include the chances at this point, but we may end up placing a 10 or 20% POP for the weekend time periods across the far Northeastern third of the area.

Early next week the southerly return flow arrives with increasing humidity and increasing temperatures.  We'll be flirting with the lower 90s by Monday and Tuesday.

 Yesterday: 94 ( new record).  Precip yesterday: 0.17 

May to date: 0.32     A departure of -4.99 from average for May.

Today's average high: 83   average low: 63

Sunrise today: 6:09AM  Sunset tonight: 8:34PM