Surprise…SURPRISE!January 30th, 2014 at 11:59 am by Don Slater under Weather
To add a little to what Jeremy has written.
As of 11:00 last night, I had predicted overnight lows to be in the single digits inland to the low teens inland. Of course, the temperatures dropped to from around -4 to around 7 or 8! So this was indeed a “blown forecast”.
Here’s a little of what was going on prior to the 11:00 newscast. Mid and high-level cloudiness was covering the region and greatly slowing the temperature drop. That cloud cover was just not budging either. With that cloud cover not clearing out, temperatures had not dropped all that much during the evening hours…basically dropping from daytime temperatures of around 23 to around 12 to 19 by late evening. In other words, no real indication of “plummeting” temperatures.
Here are a few images from last night. I screen-grabbed them off the web so image quality is not terrific, but you’ll get the idea. This first satellite image is from 10:30 last night. You will note the cloud cover over southeastern Virginia and North Carolina; that cloud cover had basically not moved since late afternoon yesterday. You might remember yesterday’s brilliant sunset. Temperatures were in the upper teens to around 20. This second satellite image is from 11:30 PM (right at the end of the newscast…uh-oh!). The cloudiness has finally shown signs of eroding. Here’s the satellite image from 12:30 AM. Cloud cover is basically gone from southeastern Virginia. With clear skies, dry air, no wind, and extensive snow cover…temperatures can now plummet!
And plummet they did! Here are 2 temperature records from National Weather Service reporting sites (screen grabs again). The first from Suffolk. You will note under the Temp. column, the -4 readings at 6:15 and 7:35! For the 11:00 (10:55) reading, it was 12 degrees. That’s a 16 degree drop by 6:15:Here are the temperature records for Norfolk for pretty much the same time frame. The 11:00 reading was 18 degrees. While the 3:51 reading was 7 degrees, we actually bottomed out at 6 degrees (presumably around 4:00 AM). So that was a 12 degree drop between 11 PM and around 4 AM!Rapidly clearing skies, no wind, dry air, and heavy snow cover. All resulting in a very rapid temperature drop…and that blown forecast.
We’re still on track to see highs in the low 30s today. We’ll see at least some of that snow melt today…a lot more by the weekend!