TULSA, Oklahoma - Grab some rain gear this morning and keep it handy through Thursday evening.  We’re tracking a few storm chances, including a few strong to severe.  Blustery weather returns Friday.

 

 A strong upper level system will swing across the Idaho-Montana region this morning before bowling across the intermountain region tonight then ejecting into Minnesota Friday evening.  This northern stream system brings a strong blast of winter weather to a large portion of the Rockies into the upper Midwest over the next few days while shoving a surface cold front into Oklahoma Thursday with strong to severe thunderstorms and some heavy rainfall threats.  The front will bring another surge of chilly to cold air Friday across NE OK and will be coldest air of the young fall season.  A light frost is possible Saturday morning with a few locations in valleys flirting with a 32 on the map.  The weekend currently appears to be a set of 5-star weather days. 

 Before this powerful northern stream arrives, a weak to moderate impulse in the southern stream is lifting out across northern OK and southern Kansas this morning and will produce a few scattered showers with a few lightning strikes.  No severe weather will occur with these spotty morning showers.  Later this evening, additional scattered storms are likely to develop as the low-level jet increases and moisture continues streaming back across eastern OK.  A few of these late evening and early Thursday morning storms could reach severe levels producing some nickel hail. 

 Strong south winds will quickly increase this morning as the pressure gradient across the plains increases as our powerful northern stream system draws closer to the plains.  This process causes the pressure to fall across the Lee of the Rockies as mass evacuates in the mid to upper levels.  The resounding surface inflow occurs from the south with our winds increasing speeds today from 15 to near 30 mph.  This will also increase low level moisture in the form of higher dew point temps and consequently bring warmer weather into the plains.  We’ll experience highs in the upper 70s north and lower 80s south today with these same conditions likely Thursday.

 

As the surface front nears, a few showers or storms will be likely early Thursday morning.  Over the years, I’ve seen a few of these become strong to severe, even in the early morning hours due to the amount of shear and lift expected across far northern OK.  That’s why we could experience a few severe storms later tonight into early Thursday morning.  The odds for severe storms will increase more so by the afternoon as the front nears the I-35 corridor, as early as the 2pm hour.  Convective potential energy is expected to be moderately high for this time of year with enough low level and deep layer shear for severe storms.  There will be a small window of time that all modes of severe weather would be possible, mostly Thursday from 4pm to 8pm before the front surges southeast and undercuts the updrafts along the leading edge of the front.  The main severe weather threats would quickly transition to damaging winds along with some heavy rainfall threats.  The potential for heavy rainfall may exist for a few pre-dawn hours across extreme eastern OK.  Combined with the antecedent soil conditions, this area will be monitored for flooding potential.  Yet, most data have trended toward a faster exit of the main system, and this should mitigate the flooding issue. 

Temperatures should take a dive Friday morning to midday with highs reaching the lower 50s along with strong northwest winds and cloudy sky before clouds will clear by the afternoon.  This will set us with a chilly to raw Friday night as temps drop into the upper 30s by Saturday morning.  Some frost is possible Saturday morning across some locations, with a few locations briefly reaching freezing Saturday morning.   The weekend looks wonderful with a surface ridge of high pressure building across the Mid-Missouri valley allowing sunny and cool weather Saturday with highs in the lower o mid-60s and near 70 Sunday.  The next front appears Monday night into Tuesday, but low-level moisture appears to stay south.  We’ll keep the period dry and pleasant for a few days early next week.

 

Thanks for reading the Wednesday morning weather discussion and blog.

Have a super great day!

Alan Crone