2008-2009 Winter Forecast

Justin's 14th Annual Winter Forecast for the 2008-2009 Season.

This forecast is for the months November through March and will include an general forecast pattern over the lower 48 states. I will also put in a little more detailed forecast in for the Ohio Valley and Texoma area. This forecast has been in the works for the past couple months whenever I got a little free time to work on it. I do occasionally read forecast predictions or case studies from other meteorologists or groups like the Climate Prediction Center. I however do not base my prediction from them but solidify my thoughts by their findings or beliefs in their forecast. I have spent the last two months reading, understanding and putting together my own forecast. So here it is, my latest winter forecast for the winter of 2008-2009 hope you enjoy it or at least read it.

The enso-neutral conditions continued during the fall season, as generally near average sea surface temperatures were observed across the equatorial Pacific Ocean. Though the enso-neutral conditions have been in place since early summer, the atmospheric circulation the western and central tropical pacific had lingering affects of a weak La Nina through early Fall. Looking ahead to the next 3 to 4 months the forecast for Nino 3.4 sea surface temperatures anomalies( difference in average over last 30 years) are in pretty good agreement. The consensus for the rest of the fall and winter season is the ENSO to remain neutral. Therefore the forecast of temperature and precipitation will not be bases on years with more than a minor El Nino or LA Nina. The Zero on the Graph equals a neutral signal with plus numbers El Nino/minus La Nina.

Over the years I continue to use analogs and they have come up very well especially the last three out of four years. As I pretty much nailed what the overall pattern would be in general for last winter and what kind of weather would dominate in certain areas of the lower 48 states. This years MEI analog years that match up with this years spring, summer and early fall season(through Sept) are 1985-1986, 1949-1950 and 1974-1975. Then I took MEI analog looks just using the Hurricane season June-Sept and came up with some very close match based on Precipitation and temperature distribution. Years 1950,1974 and 1989 were the top threes and all had very similar hurricane numbers with 15 to 17 storms and majority of landfalls being western Gulf and Carolina coast. 1985 and 1989 had very similar Falls with the aspect to temperatures in which they had drastic changes to winter come mid to late November into December.

So with no real strong La Nina or El Nino I went back and looked at this past summer and fall season weather pattern. The average trough axis during the summer was near the Mississippi River and since then it has continued to shift to the east towards the Ohio and Tennessee Valley. This trough will likely continue to move a little more east as the typical strong summer southeast ridge breaks down. Once it breaks down the winter jet, once it sets in, will tend to buckle over the Ohio and Tennessee valleys. We should also have a strong jet plowing into the Pacific Northwest, which will lead to frequent storms in the Pacific Northwest. This is another reason I like looking back at the past to predict the future. If its happened before with similar conditions why wouldn't it happen again.

The winter as a whole I believe with be a colder one from the Plains east then the past 5 years. Late November into December will likely be the coldest from normals and will likely be remembered as a very cold and snowy one from areas across the Northern Plains and area east of the Mississippi river. As this winter will be know for its start and end with a possible nice thaw in January relative to normals of course. So people in the Ohio Valley hoping for a white Christmas your odds are pretty good I think. Good sign of this happening by the end of November is the Arctic Oscillation index. Which has been positive but is showing signs of going negative quickly by mid November. For the majority of October it has been positive and that has allowed a very cold air mass to build. So when the AO turns negative like expected on the latest forecast model there will be a very large supply of cold air for the lower 48 states. Frozen Turkey anyone?

Here is a real quick map to show you were I think temperatures will break down for the winter season and now here is a break down each region of the lower 48 states.

WEST: Warm and Dry for most of the region except for the far Northwest as they will likely see a normal to slightly above normal precipitation. As there will likely be a pretty steady line of storms coming off the Pacific especially early on. California and into the southwest will likely be talking about high fire danger and drought conditions by the spring.

The Plains: Yo-yo season with frequent shots of cold arctic air with it lasting longer in the north compared to the southern Plains. Could see a couple big snows and ice storms across the Central Plains(Nebraska,Kansas and Oklahoma) with the Southern Plains(Texas Panhandle, Oklahoma) dealing with freezing rain/drizzle. Low level cold air with warmth of the southwest trying to build to the north and east. Core of the coldest air will likely be centered across the eastern part of the Northern Plains.

Southeast: Not good news as will likely continue its dry and warm pattern except I do see a possibility of a couple nice size storms(Georgia and the Carolinas) with a wetter late winter season( Feb and Mar).

Great Lakes & Ohio Valley: The snow lovers will enjoy this forecast as a cold winter is in store with some long lasting cold weather. Do see the possibility of some large storms but do see the frequent Alberta Clippers a little more likely in the cold northwest flow through the heart of the winter. A January thaw with likely help give a brief break from the cold weather.

Northeast: Noreasters and cold weather especially for the interior but the coast line will be near normal with some fights of heavy rain and snow. Analogs point to some heavy snow storms across the eastern Ohio Valley, up the Appalachian mountains and up the East Coast.

Monthly Forecast

November: Cold air starts to really take hold by the 20th across the Northern Plains into the Great Lakes. As they will likely see below normal temperatures for the month with some nice storm systems developing. They will likely be fueled by a nice contrast of temperatures with the warmest temperatures being the desert Southwest and the Southeast. Precipitation will likely be above normal from the Southern Plains east along the stormtrack to the Ohio Valley.

December: Coldest month of the Winter season compared to normals for the majority of the U.S. east of the Rockies. Large Arctic outbreaks as Arctic Oscillation shows signs it will want go negative allowing for some very cold temperatures. Another thing that will help is the expansion of snow cover that starts by late November and will really get laid down by Christmas arrives. I believe the core of the cold will come after mid month and last into January. An interesting to note the Gulf-o-centric hurricane seasons, the last three most prominent with no strong ENSO signal ('05, '89, '85 ... all with more than three named storms in the Gulf and more than 75% of the hits in the Gulf), had cold Decembers. Precipitation will likely be normal to slight below normal across the Plains. Since the stormtrack will so far south the Gulf Coast could see normal to slight above normal precipitation.

January: Cold to start the month with a January thaw likely as all analogs had slightly warmer than normal temperatures. So yes it will be cold since average high temperatures are generally at there coldest during January. The overall pattern will likely not promote Arctic outbreaks and likely be a calmer drier month then that of November and December.

February and March: Cold air lingers well into March for a good portion of the country as wave pattern starts to shorten. This will promote the frequency of storms across the nation with two prominent storm tracks. One from the northern Rockies with a lee side Low developing across the southern Plains moving northeast into the Great Lakes. The second one will likely be energy diving south across the Plains then developing a coastal storm off the east coast.

Key Points for the Ohio Valley: Warm start to November with likely an abrupt end to the warmth by the 20th. First 4+ inch snowstorm will likely arrive by the first week of December with temperatures 2 to 4 degrees below normal for December. January will be near normal with temps and Precipitation. I also wouldn't be surprised to see a very cold start be even out by a warm end of the month. February will have normal temperatures and precipitation. Temperatures will likely be colder then normal through most of March with a wet pattern. Indianapolis Averages around 24 inches of snow as I'm predicting around 26inches.

Key Points for Texoma: Very warm end of Fall will come to a crashing end by early December with frequent shots of Arctic air down the Plains. Northwest flow with occasional energy upper level energy will make things interesting. December will likely see one or two ice/snow threats with a pattern supporting overrunning precipitation. So I can see several bouts of freezing drizzle or freezing rain come by the end of December. If a storm can develop before getting east of the area an nice snow storm will be possible with the storm track especially early in the season. Texoma averages 1-3 inches from South to North and I could see a slightly above normal season for snowfall with Ice being the biggest threat.

Now here is what the Climate Prediction Center is expecting for the Lower 48 states. As you can see my winter forecast is alot different which has me wondering a little. =)