System Nearing Soon

Thursday, February 19th 2015, 4:16 am

Good morning.   Cold temperatures are greeting you again this morning across the region with lows in the upper teens and lower 20s.   South winds will return today and increase speeds by midday as a surface area of low pressure develops in the Lee of the Rockies.   Winds may gust from 20 to 25 mph along with partly cloudy conditions.   Model point soundings indicate daytime highs may reside in the lower 40s across northern OK but much warmer air will be located south across far southern OK and north Texas.   This “warm sector" may attempt to move northward Friday into Saturday before another significant cold front sweeps across the area Saturday afternoon and evening.   The exact position of the warm sector remains problematic in the data.  I continue to think most of it will reside southward until Saturday morning to midday.   The result will be only slightly warmer air for northern OK (and the Tulsa metro) Saturday morning before the cold air rushes southward bringing us back down to near or even below freezing Sunday for afternoon highs. 

As the surface area of low pressure develops today and tonight, moisture in the lowest to mid-level of the atmosphere will be brought northeast, up and over the colder air at the surface.   The result will be a low-end chance of light showers or drizzle early Friday morning to midday.   The exact position of the “warm sector" becomes critical.   Locations to the northeast of this sector will be near or slightly below freezing.  This would create a small window for light freezing rain or drizzle, but only for a very small window of opportunity.   Currently, I think this may occur across extreme eastern OK, along and northeast of the highway 412 corridor and east of highway 69-75.   The Tulsa metro would be around 32 to 33 and right on the bubble of freezing temps for a short period early Friday.   Friday afternoon highs would move into the mid-40s for the metro and surrounding vicinity, while locations across the Texoma region could see temperatures climbing into the 50s and 60s.  

Friday night into Saturday morning the low pressure area drops southeast and develops a wave along the warm sector boundary.   This should be positioned along the Red River Valley.  This creates southeast winds across southeastern OK and northeast winds across the far northeastern third of the region.   Some early Saturday morning rain will be possible near the Tulsa metro, but the activity may quickly exit the area to the east by midday.   Thunderstorms may occur early Saturday morning, for a few hours, across southeastern OK in the warm sector.  

Saturday afternoon and evening, colder air to the north begins rapidly moving southward and our quasi-stationary warm front to the south begins moving east and southeast.   Strong thunderstorms may be possible along and ahead of the boundary located across southeastern OK and southwestern Arkansas for a few hours Saturday afternoon.   Locations near Tulsa will experience a rapid drop in temperatures, from near the mid-50s into the 30s by late Saturday evening, along with strong north winds at 20 to 35 mph.   Most, it not all of the moisture, will be quickly exiting the area Saturday evening.   But as the colder air deepens, any remaining moisture could transition to some light snow.   I continue to think this scenario remains a low chance for pre-dawn Sunday morning, but a chance that will need to monitor carefully.

Sunday into Monday cold air will dominate the region with highs Sunday near 30.   Morning lows Monday would start in the teens and end in the lower to mid-30s.   A brief warm-up is likely Tuesday into Wednesday next week before a very cold air mass slides southward into the state Thursday and Friday.   Once again, extended model data suggest a potential for wintry weather during this period of late next week.   If you're a frequent reader of the morning discussion, you'll know my “standard " dis-claimer:   This portion of the forecast is subject to big changes, so check back often.   We're many days out and things can and will change.   

Thanks for reading the Thursday Morning Weather Discussion and blog.

Have a super great day!

Alan Crone