Unfortunately, I have bad news once again. Chances are becoming slimmer for a white christmas. I am very sorry to say this, as we close out December, most if not all meteorologists long-range forecasts were wrong for the month of December. Currently, most of the United States will close the month out well above normal. Initial forecasts way back in October were saying that because it would so cold in the Midwest this December, they were expecting below normal precipitation, but above normal snowfall. As you can see, we had just the opposite. Instead of cold temperatures and well below normal precipitation, like last December, temperatures will close out December three to five degrees above average for the month. This overall warmth, has lead to a very low snowpack across the country. In fact, it may be the lowest snowpack the United States has seen in December since 2006, with only 25.6% of the country covered with measurable snow. Another opposite that was seen in December, was above normal precipitation. So far this December, we have seen nearly 3 inches of precipitation, not near as much as November, but still far above normal. Currently, we are about 1.5 inches above normal for December. The above normal precipitation throughout the year, has lead to some pretty impressive anomalies (departure from normal). Right now, 2011 is the third wettest year on record at Fort Wayne, with nearly fifty inches of rain (or snow) fallen. For comparison, this is the normal amount that places such as Central Florida receive in one year, and we have had more rain than many places in Florida this year. The exact total for this year is 48.73 inches, which is well above what last year's precipitation total was, which was 32.46 inches. If long-range models and forecasts are correct, I expect well above normal precipitation to continue through at least the first seven months of next year also.
Now for the white christmas forecast, as the current storm system moves out, not much of a cool down will take place, with another storm system tomorrow, causing temperatures to remain in the upper 30's and lower 40's. Actually, temperatures on Thursday will remain steady throughout the day, then dropping in the afternoon, into the lower 30's by nightfall. With the next storm system, we could end with a period of snow Thursday night, as temperatures will be in the upper 20's, and the 540 line (5400 meter thickness between the 1000 millibar layer and the 500 millibar layer, usually indicating the rain/snow line) will be well south of the area, leading to a period of accumulating snow, especially east of Fort Wayne. On Friday, temperatures will drop into the mid 30's under mostly to partly cloudy skies, as the next storm system from the Gulf of Mexico moves northeast into the East. The problem is that, this storm was originally forecast to bring us some light snow on Saturday, which does not look likely anymore, as the storm will be too far to the east. Temperatures also do not look as cold as it originally did. By Christmas Day, a few snow showers will be scattered throughout the area bringing surprise white Christmas's to a few areas. Highs that day will be in the lower 30's and possibly colder, even though the National Weather Service is forecasting temperatures in the mid to upper 30's, I do think that this arctic air mass will be cold, and even cold enough to produce lake-effect snow. By next week, yet another warming trend, but not as much as the last warming trend (into the lower 40's and upper 30's), with some periodic arctic air masses moving into the area through New Year's Day. By New Year's Day, a new set of storm systems will be affecting starting once again the pattern of heavy precipitation, and once again this is where the long-range gets tricky.
Yesterday, I mentioned some of the tid bits in the long range. I did never get to mention the ENSO, so here goes. According to the latest climate forecast models, the La Nina will continue to strengthen, possibly becoming a strong La Nina around -1.7. According to the CFS, CFSv2, and the GFDL, they expect the La Nina to peak in strength around March, even though their respective forecasts vary in intensity. The CFS is forecasting a peak around -1.9, the CFSv2 around -1.4, and the GFDL around -1.8. If you average these values, you get -1.7. As for precipitation and temperature extremes, the models are all varying from each other, so it probably isn't that wise to treat these forecasts as truth. The CFS is forecasting a rather warm January, for the area, while in February and March, temperatures drop well below normal, leading to a very snowy end to winter. The CFSv2, is forecasting above normal temperatures through June, with only slightly below normal temperatures for February. As for precipitation, almost all of the models agree that precipitation will be well above normal for the next five months, leading to continued flooding problems, and possibly severe weather problems in April and May. With the strengthening of the La Nina, I expect that this forecast will hold true. But as for the next month, I have looked at the teleconnections and this is my good news (for snow lovers that is). The NAO is expected to gradually drop into negative territory, allowing all that extensive cold in Canada to drop southward finally. At the same time, even though there is less agreement among models on what the AO will do, there is a general downward trend in its values also, becoming negative by about January 1st, and continuing its downward turn. The PNA, at the same time, will become positive, which is conducive to a west coast ridge, and east coast trough. All of these factors, if these forecasts are correct, will converge right around January 1st, possibly making January a very cold and snowy month around here. All of these factors, combined with the La Nina, will cause a very interesting middle and end to winter. Not only will these factors converge, but also, solar output will also be taking a dip, leading to colder temperatures and therefore snowier days, instead of rain. All of this could have serious consequences in the spring, because I am expecting major flooding this spring, even more so than last year. This is my update, for more updates, tomorrow I will try to have an update.
Now for the white christmas forecast, as the current storm system moves out, not much of a cool down will take place, with another storm system tomorrow, causing temperatures to remain in the upper 30's and lower 40's. Actually, temperatures on Thursday will remain steady throughout the day, then dropping in the afternoon, into the lower 30's by nightfall. With the next storm system, we could end with a period of snow Thursday night, as temperatures will be in the upper 20's, and the 540 line (5400 meter thickness between the 1000 millibar layer and the 500 millibar layer, usually indicating the rain/snow line) will be well south of the area, leading to a period of accumulating snow, especially east of Fort Wayne. On Friday, temperatures will drop into the mid 30's under mostly to partly cloudy skies, as the next storm system from the Gulf of Mexico moves northeast into the East. The problem is that, this storm was originally forecast to bring us some light snow on Saturday, which does not look likely anymore, as the storm will be too far to the east. Temperatures also do not look as cold as it originally did. By Christmas Day, a few snow showers will be scattered throughout the area bringing surprise white Christmas's to a few areas. Highs that day will be in the lower 30's and possibly colder, even though the National Weather Service is forecasting temperatures in the mid to upper 30's, I do think that this arctic air mass will be cold, and even cold enough to produce lake-effect snow. By next week, yet another warming trend, but not as much as the last warming trend (into the lower 40's and upper 30's), with some periodic arctic air masses moving into the area through New Year's Day. By New Year's Day, a new set of storm systems will be affecting starting once again the pattern of heavy precipitation, and once again this is where the long-range gets tricky.
Yesterday, I mentioned some of the tid bits in the long range. I did never get to mention the ENSO, so here goes. According to the latest climate forecast models, the La Nina will continue to strengthen, possibly becoming a strong La Nina around -1.7. According to the CFS, CFSv2, and the GFDL, they expect the La Nina to peak in strength around March, even though their respective forecasts vary in intensity. The CFS is forecasting a peak around -1.9, the CFSv2 around -1.4, and the GFDL around -1.8. If you average these values, you get -1.7. As for precipitation and temperature extremes, the models are all varying from each other, so it probably isn't that wise to treat these forecasts as truth. The CFS is forecasting a rather warm January, for the area, while in February and March, temperatures drop well below normal, leading to a very snowy end to winter. The CFSv2, is forecasting above normal temperatures through June, with only slightly below normal temperatures for February. As for precipitation, almost all of the models agree that precipitation will be well above normal for the next five months, leading to continued flooding problems, and possibly severe weather problems in April and May. With the strengthening of the La Nina, I expect that this forecast will hold true. But as for the next month, I have looked at the teleconnections and this is my good news (for snow lovers that is). The NAO is expected to gradually drop into negative territory, allowing all that extensive cold in Canada to drop southward finally. At the same time, even though there is less agreement among models on what the AO will do, there is a general downward trend in its values also, becoming negative by about January 1st, and continuing its downward turn. The PNA, at the same time, will become positive, which is conducive to a west coast ridge, and east coast trough. All of these factors, if these forecasts are correct, will converge right around January 1st, possibly making January a very cold and snowy month around here. All of these factors, combined with the La Nina, will cause a very interesting middle and end to winter. Not only will these factors converge, but also, solar output will also be taking a dip, leading to colder temperatures and therefore snowier days, instead of rain. All of this could have serious consequences in the spring, because I am expecting major flooding this spring, even more so than last year. This is my update, for more updates, tomorrow I will try to have an update.
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