WRAL WeatherCenter Blog

Warming Some, and Bouncing Light

Posted February 19, 2007

Last week I mentioned the potential for a shift to mainly normal to above normal temperatures setting in for the middle and end of this week, and so far we appear to be on track for that to occur, although as usual there is some disagreement beyond the next couple of days among computer models as to whether we will hover just a little on the warm side of normal (mid 50s or so this time of year) or swing beyond the usual departures from normal into the upper 60s to around 70 or so. In all cases, it appears we'll stay too warm into the weekend for any frozen precipitation.

There was actually a little of that over the northeastern half of our viewing area Sunday afternoon and evening, as we closed out the weekend with the passage of a strong, but moisture-limited upper level disturbance that swept southeastward across the area accompanied by very cold air just a few thousand feet off the ground. This destabilized the air yesterday afternoon and caused a layer of clouds to develop for a few hours. The fact that those clouds were at the correct temperature for rapid growth of dendritic snow crystals helped them to develop precipitation sized particles that led to plumes of radar echoes drifting toward the southeast, but the cloud bases were around 5-8,000 feet above the ground and dry air below prevented much if anything in the way of surface sprinkles or flurries around here. I was able to find a brief period of light snow at the surface last evening reported at Currituck, and a few likely flurries at Cape Hatteras closer to midnight. The same system helped to enhance already blustery winds across the area late yesterday, and we had wind gusts to 35 mph at Fayetteville, 40 mph at Raleigh-Durham, and a 45 mph gust at Greensboro, while sustained winds (2-minute averages) mainly ranged about 12-20 mph.

Occasionally, we like to throw in a reference to something a little off-topic here, but that we find interesting. That is what the "Bouncing Light" in the title speaks to, as well as the image above. It is something I ran across while browsing a Hubble Space Telescope gallery, and involves a series of images taken a few years back by the Hubble of a star, about 20,000 light years from us, that inexplicably expanded for a brief time, became the brightest star in the Milky Way, and then subsided, all without shedding mass as astronomers would expect of a Nova. Once this had happened, an expanding spherical "shell" of bright light continued to flow away from the star, and then to reflect off of successive layers of dust in the space surrounding the star. These "light echoes" made for a fascinating series of images, and some astronomers likened the event to being able to see a "CAT scan" of the dust in the vicinity of the star. Here are some links to more resources about this event for those who are interested:



Please with your WRAL.com account to comment on this story. You also will need a Facebook account to comment.

Oldest First
View all
  • g88ky Feb 22, 2007

    Ahhhh, and don't worry fellow weather nerds, for we shall strike fear in the heads of no one as long as our forecasts from the local yokels continue to be about as correct as they always have been. 10 out of 312 ain't bad!
    And Huey is gooey, but you can bet yo' bootie that he says pooie to all that he comes in contact with.
    As sure as he'll vote for Hilary and then Giddy G. as VP we're all in good hands!
    ;c )

  • yukonjohn3 Feb 22, 2007

    As my family and friends in NC have noticed for the last 25 years, when it is on one side of normal on the east coast, it is totally on the other side of normal in the interior of Alaska. While you guys were having your cool weather a week or so ago, it was downright balmy here. Now that it has warmed up there, it is FREEZING here. Our temperatures are running 25 to 30 degrees below normal here. That is pretty significant seeing how the averages are 10 above zero for the high and 15 below zero for the low. Its 38 below here tonight and still dropping like a rock. I talked to Greg O'Fischel about this pattern several years back and it actually has some basis for fact in the way the jetstream normally works. So, bottom line, look for WARM weather there for the next several days at least!!

  • Huey Feb 21, 2007

    Don't you worry, fellows, cause g88ky, he's the best!
    He knows, he just knows, where those isobars will be come
    day after tomorrow. Greg and his gang live in fear that
    ole g88ky will someday replace them in the weather center.

  • ajstarrrn Feb 20, 2007

    Ahhhhhhhhhhhhhhhhhhhhhh!!!!!!!!Another inspiring comment from g88y!!!!!!!

  • jmgray112 Feb 20, 2007

    Hurricane Season !!!!!!

  • g88ky Feb 20, 2007

    Ahhhhhhhh, another successful winter here in the triangle.
    We were SO lucky to scoot by with no real snowfall and thank goodness.
    Only 14 predictions for winter precip, none of which came to pass, good record guys!
    What would the triangle do with REAL winter weather?
    Buy all the bread & milk?
    Sit for miles & miles and hours & hours on I-40 on top of 1/10th of an inch of nothing?
    Cancel schools for no reason so that the kids can make it up with 48 hrs. notice? Make the news anchors nervous that they might have to ad lib with continuous & ridiculous coverage that no one watches? Wheeeeeeeeew, close call.

    Now that Spring has arrived what are we going to talk about for the next 10 months?