Thursday, 22 Sept 2011 Extended Pow County Forecast

The early Fall pattern continues into the weekend as an upper level low pressure system spins over the Great Lakes.  Temps will remain below seasonal normals with weak north winds and increased clouds this afternoon.  Temps will modify slightly to near 70 by Saturday, before rising into the Low 70's early week, and near 80 by Wed the 28th.

By next Thursday, the pattern goes more unsettled as strong Low Pressure develops in the Nebraska Panhandle.  We should remain Dry Thursday and Friday, but gusty south winds will usher in 80+ Degree temps and plenty of low level moisture.  Expect a strong cold front to push into Iowa late on Saturday (Oct 1st), or Sunday.  We should see some much needed Rain.  At the same time, temperatures will drop well below normal once again in strong north winds.
 


Today thru Wed 22nd - 28th: Mainly Dry thru the period (may see a shower late Sunday) with High Temps ranging from the Low 60's to near 70 by the weekend, Low 70's by Monday, to near 80 Wed. Low Temps will increase from the Upper 30's Friday morning to near 50 Monday.

Thursday thru Thursday 29th - Oct 6th:  Dry and Breezy the 29th/30th with temps in the Low 80's - Windy and Rain on the 2nd/3rd with temps near 60 - .

Fri and Sat 7th/8th: Dry and Cooler.

Note: May see our First Hard Freeze around the 10th.

Winter 2011/12.

The basis for my forecast is the likely formation of a weak La Nina (cooling waters in the South Pacific) forming and continuing through the winter. Last years "strong" La Nina combined with high pressure over the North Atlantic lead to heavy snows across the Midwest and Northeast. Subtle changes will take place in the weather pattern (primarily a weakening dome of high pressure over the southwest U.S.) that force systems west to east out of the Central U.S. Rocky Mountains, causing a major dip in the jet stream over the eastern half of the country (East of the Miss River). This pattern would put Iowa at the leading edge of a storm track that would give us near normal temperatures leading into winter, and below normal temperatures going out. It would put the north and west 2/3 of the state slightly above normal for precipitation, and the south and east 1/3 of state at, or slightly below normal.


Iowa Winter Weather:

The southeastern 1/3 of Iowa will see Near Normal Snowfall, while the rest of Iowa will see 3-5 inches Above Normal.



What will the Winter of 2011/12 bring?
Here's my best guess right now. I'll refine it as time goes on. It may change - but it won't change a lot.......


Pow County will see Seasonal "Average Daily" Temps up thru Dec - then Jan, Feb, and Mar will be 3 Degrees Below Average.


Nov:
Average Snowfall - 2.1"
Forecast - 2.5"

Dec:
Average Snowfall - 6.5"
Forecast - 7.5"

Jan:
Average Snowfall - 8.1"
Forecast - 10"

Feb:
Average Snowfall - 7.2"
Forecast - 8.5"

Mar:
Average Snowfall - 3.8"
Forecast - 4.5"

Our Average Snowfall between November and March is 27.7". I'm forecasting a Total Snowfall of 33.0" - which is 5.3" Above Normal for the time period.

April: We'll see an inch or two early April.