Tracking Two Weekend Waves

Friday, November 14th 2014, 4:39 am

By: Alan Crone

Our main issue continues to be the prospect for some type of wintry weather for the weekend as we track two separate waves into the region.   Most of the models indicate our chances for precipitation should remain very low. But we think the second wave continues to be stronger (Sunday) and a little more bullish with the potential for some minor accumulation across the region.   Our forecast will continue to offer a blend of available data with a “nod" to Sunday afternoon having the better chance for some light snow in northern OK.    We do anticipate some precipitation across the region beginning Saturday across southern Kansas and then ending Sunday across part of Oklahoma as the second wave exits the region. Another significant surge of arctic air rolls into the state Sunday morning along with gusty north winds. This cold air will stick around until Tuesday before the upper air pattern changes allowing the main upper air vortex across the Great Lakes region to move eastward. Warmer air will move back into the state from the southwest Wednesday through the end of the week. We may also have another short wave approaching by the end of the week increasing the rain chances for eastern sections of the state.

Temperatures this morning have dropped into the mid and upper teens due to the presence of extremely dry air, relatively light wind, and partly cloudy conditions. Our surface wind direction will remain from the northeast this morning before backing from the southeast this afternoon in response to falling pressure across the Rockies as the next short wave approaches the region.   Daytime highs could hit the 40 mark, but we'll probably stick with some upper 30s for many locations across the eastern third of the state. Friday Night Football games will be very cold with play-off football starting in the lower 30s and finishing around 28 to 30 for the end of the game. Games will be dry statewide.

There remain several small but important details to be discovered regarding the weekend system. I don't think we'll a lot of precipitation Saturday, but some will fall near northeastern OK and more so into Southern Kansas. No significant accumulation or travel impacts are anticipated for our immediate areas based on the current timing (midday to early afternoon) for this possible event.   If the system is slightly faster, some minor early Saturday morning travel may be impacted on bridges and overpasses across extreme northern OK with Saturday morning temps expected in the upper 20s.   This first wave will rapidly move eastward away from the state Saturday afternoon and evening.   One item of note is the presence of a southeast wind Saturday. It's very difficult to get any significant wintry weather precipitation with southeast surface winds across eastern OK. It does happen, but it's rare.    Most models are indicating that portions of eastern Kansas would have a better shot of a few inches of snowfall.

Our Saturday chance remains around 20% for northern OK and about 50% for southern Kansas.

The second wave (and stronger system) will be dropping into the area Sunday helping to shove a surface cold front southward bringing gusty north winds and much colder air back to the state. Here's where the model discrepancy is pronounced due to some inconsistency in run to run output.    We have been in the 30 to 40% chance category for the Sunday event and have been advertising “light snow" with no significant accumulation.    Some model output would be in the range of an inch or two, and we'll continue to keep the headlines consistent for Sunday, at least at this point. This means a dusting will be possible but the chances of any accumulation over an inch would be somewhat low. Our chances for Sunday precipitation will increase to near a 50% chance. This Sunday portion of the event could warrant some winter weather advisories for the area from our friends at the National Weather Service.

The cold arctic air mass will remain across the state Monday and Tuesday with well below seasonal average temperatures before moving eastward Wednesday.

I obviously encourage you to remain aware of the weather conditions this weekend.

Thanks for reading the Friday Morning weather discussion and blog.

Have a super and safe weekend.

Alan Crone

KOTV