Wed, 21 Sept 2011 Extended Pow County Forecast

Low Pressure over Mn will drift east into Northern Michigan resulting in strong northerly flow over Iowa today.  Expect increasing clouds, but dry and breezy in Pow County thru the morning - may see some sprinkles near and northeast of Iowa City thru the afternoon. 

Low Pressure will move east by Thursday and a very dry pattern will set up for at least the next 10 days as High Pressure anchors itself over the Great Lakes Region.  This will result in Clear to Partly Cloudy skies, light winds, and seasonally cool temperatures with highs in the low/mid 60's and lows dropping to the high 30's by Friday morning.  However, I'm not expecting any frost in Pow County thru the week.  Temps will be more seasonal by the weekend.   


Today 21st:  Becoming Mostly Cloudy - Dry and Breezy - Temp 65.

Thursday thru Wed 22nd-28th:  Dry thru the period with High Temps ranging from the Low 60's to Upper 60's by the weekend, and Low/Mid 70's by Monday. Low Temps will increase from the Upper 30's Thursday to the Low 50's Monday.

Thursday thru Thursday 29th - Oct 6th:  Dry and Warmer - Breezy with a Shower on the 4th/5th - High Temps from High 70's to Low 80's.

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 Moutains, 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 alot.......


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"
Forercast - 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.