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Dr. Tim Coleman
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A strong cold front dropped temoeratures from the 70s at 7 pm last night to the 40s by 1130 pm. The cold air will get deeper through Saturday, with highs today in the 50s and tomorrow it will stay in the 40s most of the day. Lows will drop below... Continue reading
Posted 2 hours ago at WBRC Weather
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What a nice day today! Temperatures in the upper 70s and lower 80s with partly cloudy skies. It looks like summer. The sun is getting stronger too. Here is the chart from the UAH pyranometer the past two days. The dips are when clouds go by, but notice around 1730... Continue reading
Posted 2 days ago at WBRC Weather
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The above chart shows the amount of solar energy coming in each day, in kilowatt hours per square meter, at the top of the troposphere throughout the year (so it assumes clear skies). It's pretty accuare at the ground when it is sunny, but with clouds the actual values can... Continue reading
Posted 7 days ago at WBRC Weather
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The spring equinox occurs today at 2245 GMT (5:45 pm CDT). So today the entire world gets 12 hours of day and 12 hours of night. It's nice to see spring this year after the long cold. Due to the rotation of the earth around the sun, the sun has... Continue reading
Posted 7 days ago at WBRC Weather
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The above photograph is a still shot from a camera (I think in England) from 0934 GMT (4:34 am CDT) this morning. A total solar eclipse occurred at a few points for a few minutes, but the moon was in front of at least 50% of the sun over a... Continue reading
Posted 7 days ago at WBRC Weather
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Above is the temperature plot from the Birmingham airport from 2 pm last Wednesday through 2 pm last Thursday. A really strong cold front moved through overnight, dropping temperatures from the upper 70s Wednesday afternoon, into the 30s by 10 am Thursday. Then, moisture came in Thursday and brought freezing... Continue reading
Posted Mar 13, 2015 at WBRC Weather
It's not like you need me to tell you, but we had a very cold February. A very cold pattern set up in the middle of February, with three straight weeks of cold air starting around Tuesday the 10th. Our average high temperature in Birmingham was 50.2, the 7th coldest... Continue reading
Posted Mar 13, 2015 at WBRC Weather
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It suddenly got cooler today! But, it's only temporary, and it's still in the 50s (not the 20s like last week). Air normally flows clockwise around a high pressure area, but today the high pressure area is centered over the northeast U.S., and the air can't quite make it over... Continue reading
Posted Mar 13, 2015 at WBRC Weather
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The last area of heavier precipitation is moving over the Tuscaloosa and Birmingham metro areas right now. It is mainly falling as sleet, with some freezing rain and a few snowflakes. With the cold north winds and initial melting of sleet, temperatures have dropped below freezing in much of Jefferson... Continue reading
Posted Mar 5, 2015 at WBRC Weather
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The cold front moved through Birmingham around 8:30 pm. The temperature has already dropped from the high temperature, 79 degrees, to 53 at 10 pm, and it will continue to drop quickly. It's already down to 41 in Huntsville and 31 in Nashville. We're having a few showers along and... Continue reading
Posted Mar 4, 2015 at WBRC Weather
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The National Weather Service has issued a Winter Storm Warning for tomorrow for the pink area, as far south as Lamar, Fayette, and Walker counties. South of there, a freezing rain advisory is in effect for Tuscaloosa, Jefferson, and Shelby counties and others. Very cold air, currently over Misouri, Illinois,... Continue reading
Posted Mar 4, 2015 at WBRC Weather
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The above graphic shows the chance (according to the NWS) of receiving 0.10" or more of freezing rain in the 24 hours ending at 6 pm Thursday. It is consistent with our maps from the past couple of days, with the greatest ice impacts probably in northwest Alabama, in areas... Continue reading
Posted Mar 4, 2015 at WBRC Weather
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Oh no, not again. There is another brutally cold air mass headed toward Alabama from the north later this week. We will warm up to near 70 degrees tomorrow and Wednesday, and then one of the strongest cold fronts I have seen in a while (in terms of rapid temperature... Continue reading
Posted Mar 2, 2015 at WBRC Weather
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Mary Jane Tingle sent me this picture of clouds in regular lines from about 930 am Saturday morning along I-59 in Greene County, looking north. Observations indicate clouds at 12,000 and 20,000 feet that morning at BHM. It looks like these are wave clouds being caused by Kelvin-Helmholtz instability (a... Continue reading
Posted Mar 2, 2015 at WBRC Weather
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Above is a map I put together based on snow reports from the National Weather Service and social media. This was quite a snowstorm! The 3rd largest snow ever in Huntsville. These snowstorms usually have a sharp cutoff, and this one was no exception. Notice that locations like County Line,... Continue reading
Posted Feb 26, 2015 at WBRC Weather
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It's finally snowing in the Birmingham area! The last of the precipitation across Alabama is moving through now. And finally the south winds aloft that have kept the snow just north of Birmingham all day have changed. It is now snowing across much of Jefferson County and parts of Shelby... Continue reading
Posted Feb 25, 2015 at WBRC Weather
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A large area of precipitation continues over the southeastern U.S., as a low pressure area moves south of the Gulf Coast. So far here in central Alabama, it has mainly been rain with some sleet, but some icing is occurring, mainly at higher elevations. Quite a bit of precipitation is... Continue reading
Posted Feb 25, 2015 at WBRC Weather
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The precipitation has arrived. Our low has formed in the Gulf of Mexico, and precipitation will continue into this evening. So far, the atmosphere is too warm over central Alabama for snow to fall, it is all melting in a warm layer aloft. We've been expecting that. Here is the... Continue reading
Posted Feb 25, 2015 at WBRC Weather
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NWS has issued a Winter Storm Warning for the areas in pink above, including the northern half of Alabama. This is a very difficult forecast, because there will be a fairly sharp contrast between 4" of snow in one place and no snow 50 miles down the road. Meteorologists and... Continue reading
Posted Feb 24, 2015 at WBRC Weather
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There is a huge difference right now between the NAM and other models on the rain/snow line. The NAM shows it being just north of BHM, all the others south. What the NAM is looking at is the warm nose of air at 850 mb that is already moving in... Continue reading
Posted Feb 24, 2015 at WBRC Weather
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The National Weather Service has issued a Winter Storm Warning for tomorrow for much of the Fox 6 viewing area, including Birmingham metro, Tuscaloosa, Anniston, and Gadsden and all points north. The classic setup for snow in Alabama is finally coming together for the first time in a while, with... Continue reading
Posted Feb 24, 2015 at WBRC Weather
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Above is a chart of temperature, dewpoint, and wind at various stations across Alabama, Mississippi, and Tennessee. The red numbers are temperatures, green are dewpoint, and flags are direction of wind. At BHM, temperature has dropped to 35 and dewpoint is 29. In HSV, temperature 34 dewpoint 19. The dry... Continue reading
Posted Feb 23, 2015 at WBRC Weather
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The next leg of precipitation is moving into central Alabama now. It is sleeting in many parts of the BHM metro area, including here in Trussville. Fortunately, the sun came out earlier and warmed temperatures to near 40, so there should be no problems for the afternoon rush hour here... Continue reading
Posted Feb 23, 2015 at WBRC Weather
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The National Weather Service continues a Freezing Rain/Winter Weather Advisory for areas north of 59, including BHM. A large area of precipitation is moving into northern Alabama out of Mississippi tonight. At the same time, cold air is moving south through Alabama. It is 40 in BHM right now, but... Continue reading
Posted Feb 22, 2015 at WBRC Weather
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This week will bring more very cold temperatures, as wave after wave of Arctic air continues to flow into the southeast. We actually have a cross-polar flow, where air blows from Siberia over the north pole and into North America. In the map above, the gray lines define the prime... Continue reading
Posted Feb 22, 2015 at WBRC Weather