A-L-E-K Posted October 18, 2012 Share Posted October 18, 2012 it's not going to snow in WI tomorrow...give it a couple more weeks Link to comment Share on other sites More sharing options...
turtlehurricane Posted October 18, 2012 Share Posted October 18, 2012 :weenie: Even if you just mean thundergraupel, that is quite a weenieish statement imo. The chances that temps are just right and the precip rates enough are quite low, as Chistorm has also stated. Even so, if it happened, it would be difficult to term it "thundersnow" if it was just sleet or graupel. Precipitation rates would be moderate to heavy in a thunderstorm, it would be snow and graupel if there was little melting in the boundary layer, which is possible with 850 temps 1-2 °C below freezing. There wouldn't be any sleet in a setup like tomorrow. I'm glad you guys have figured out the weather, but this is a complex scenario tomorrow from my perspective, and considering how poorly the boundary layer is modeled I wouldn't blindly take the model precip types and boundary layer temps. The free atmosphere temps (850 and above) on the other hand are modeled much better. Link to comment Share on other sites More sharing options...
wisconsinwx Posted October 18, 2012 Share Posted October 18, 2012 Precipitation rates would be moderate to heavy in a thunderstorm, it would be snow and graupel if there was little melting in the boundary layer, which is possible with 850 temps 1-2 °C below freezing. There wouldn't be any sleet in a setup like tomorrow. I'm glad you guys have figured out the weather, but this is a complex scenario tomorrow from my perspective, and considering how poorly the boundary layer is modeled I wouldn't blindly take the model precip types and boundary layer temps. The free atmosphere temps (850 and above) on the other hand are modeled much better. I agree that graupel is quite likely in spots, but you're the one calling for a chance of "thundersnow" lol. Link to comment Share on other sites More sharing options...
wxman1952 Posted October 18, 2012 Share Posted October 18, 2012 Had some thunder and lightning tonight. First in awhile. No snow or graple here yet this season. Eager to see some. Mike Link to comment Share on other sites More sharing options...
hm8 Posted October 18, 2012 Share Posted October 18, 2012 Raining pretty good here for stratiform. Link to comment Share on other sites More sharing options...
Hoosier Posted October 18, 2012 Share Posted October 18, 2012 It's close enough to not completely blow off the chance of some wet flakes mixing in but the coverage is just going to be limited at best. Temps in the lowest km are scorching relatively speaking, the atmosphere will be pretty much saturated...there is no room for evaporational cooling so you are relying on heavy enough precip rates in any one spot. There might be a decent chance if you were looking out the window at the top of the Willis tower but otherwise it's going to require a lot of luck. Link to comment Share on other sites More sharing options...
turtlehurricane Posted October 18, 2012 Share Posted October 18, 2012 I agree that graupel is quite likely in spots, but you're the one calling for a chance of "thundersnow" lol. Thundersnow = thunder + snow. So a bit of snow and thunder during a cell generated by steep lapse rates tomorrow would be considered thundersnow. It's not that big of a deal. If boundary temperatures are a little above freezing we'll have graupel and snow mixed, if temps are solidly above freezing below 850 through the column there will only be some graupel in the heaviest parts of the cell. Link to comment Share on other sites More sharing options...
Geos Posted October 18, 2012 Share Posted October 18, 2012 Precipitation rates would be moderate to heavy in a thunderstorm, it would be snow and graupel if there was little melting in the boundary layer, which is possible with 850 temps 1-2 °C below freezing. There wouldn't be any sleet in a setup like tomorrow. I'm glad you guys have figured out the weather, but this is a complex scenario tomorrow from my perspective, and considering how poorly the boundary layer is modeled I wouldn't blindly take the model precip types and boundary layer temps. The free atmosphere temps (850 and above) on the other hand are modeled much better. Not impossible I guess. If snow were to make it to the ground I would expect it over the higher terrain west and north of Madison. The 4km NAM was showing snow making it to the ground out by Sioux Falls, and Sioux City. Getting waves of moderate rain swinging through. Should pick up 0.5" no problem through midnight. Link to comment Share on other sites More sharing options...
turtlehurricane Posted October 18, 2012 Share Posted October 18, 2012 Wind gusts in mph on the Great Plains, cold air is screaming in from the north. 850 mb 0 °C line has made it into northwest Iowa. Link to comment Share on other sites More sharing options...
Chicago Storm Posted October 18, 2012 Share Posted October 18, 2012 Precipitation rates would be moderate to heavy in a thunderstorm, it would be snow and graupel if there was little melting in the boundary layer, which is possible with 850 temps 1-2 °C below freezing. There wouldn't be any sleet in a setup like tomorrow. I'm glad you guys have figured out the weather, but this is a complex scenario tomorrow from my perspective, and considering how poorly the boundary layer is modeled I wouldn't blindly take the model precip types and boundary layer temps. The free atmosphere temps (850 and above) on the other hand are modeled much better. Pretty sure no one is blindly using model precip type. It's not only how model guidance is projecting UA/boundary layer temps, but prior history and knowledge on these types of setups. The fact of the matter is that if it occurs it will be isolated at best. Link to comment Share on other sites More sharing options...
cyclone77 Posted October 18, 2012 Share Posted October 18, 2012 Pretty impressed by the wind reports coming out of the Dakotas today and tonight. Even now parts of those areas are getting 55+mph gusts. Due to the track of the surface low we never will get in to the strong winds here. Picked up 0.67" of rain late afternoon and early evening. Already over 2.5" for the month, so we're doing much better than last month. Link to comment Share on other sites More sharing options...
Hoosier Posted October 18, 2012 Share Posted October 18, 2012 Pretty impressed by the wind reports coming out of the Dakotas today and tonight. Even now parts of those areas are getting 55+mph gusts. Due to the track of the surface low we never will get in to the strong winds here. Picked up 0.67" of rain late afternoon and early evening. Already over 2.5" for the month, so we're doing much better than last month. Yeah they are going to get blasted in the northern Plains. Shouldn't have trouble seeing some gusts over 60 mph tomorrow. Link to comment Share on other sites More sharing options...
cyclone77 Posted October 18, 2012 Share Posted October 18, 2012 Yeah they are going to get blasted in the northern Plains. Shouldn't have trouble seeing some gusts over 60 mph tomorrow. Talk about a long duration wind event. Link to comment Share on other sites More sharing options...
Hoosier Posted October 18, 2012 Share Posted October 18, 2012 Talk about a long duration wind event. Just noticed that 78 mph report out there. Wow. Link to comment Share on other sites More sharing options...
cyclone77 Posted October 18, 2012 Share Posted October 18, 2012 Very strong winds making it into Iowa now. Estherville reporting 52mph gusts. Link to comment Share on other sites More sharing options...
wisconsinwx Posted October 18, 2012 Share Posted October 18, 2012 Having a cold Halloween is nice, just like having a White Christmas is nice, perfect kind of entrance into the wintry time of year. Link to comment Share on other sites More sharing options...
turtlehurricane Posted October 18, 2012 Share Posted October 18, 2012 0.62" of rain today, things have cleared out and the temperature is slowly dropping, 52 °F at the moment. The high for Thursday will occur at midnight. Very strong winds making it into Iowa now. Estherville reporting 52mph gusts. HRRR gives a good idea of who will get high winds and who won't, northern Illinois, Wisconsin, and most of Minnesota are going to stay near the center of the low where the pressure gradient is weak. http://rapidrefresh.noaa.gov/hrrrconus/jsloop.cgi?dsKeys=hrrr:&runTime=2012101800&plotName=gust_t210m&fcstInc=60&numFcsts=16&model=hrrr&ptitle=HRRR%20Model%20Fields%20-%20Experimental&maxFcstLen=15&fcstStrLen=-1&resizePlot=1&domain=t2&wjet=1 Link to comment Share on other sites More sharing options...
Hoosier Posted October 18, 2012 Share Posted October 18, 2012 Having a cold Halloween is nice, just like having a White Christmas is nice, perfect kind of entrance into the wintry time of year. Big Halloween snowstorm is one thing I'd love to experience. Will probably have to go somewhere else though because it might be 200 years before it happens in LAF. Link to comment Share on other sites More sharing options...
Geos Posted October 18, 2012 Share Posted October 18, 2012 Got kind of ripped off on the rain tonight. Only 0.34". Just some mist right now. Better luck with instability showers over the next 2 days. Fall color is at it's peak right now around here. Good thing it won't be too windy, otherwise a lot of the color would vanish by the weekend! Link to comment Share on other sites More sharing options...
SpartyOn Posted October 18, 2012 Share Posted October 18, 2012 Saw my 1st flakes this past Sat. I believe DMC & Jonger did also. Obviously they mixed with the rain for a short time, but its only fitting to wish the luck my west! Link to comment Share on other sites More sharing options...
cyclone77 Posted October 18, 2012 Share Posted October 18, 2012 Leaves are no doubt well past peak around here. The countryside was far more colorful a week or two ago. The only trees that are colorful now are some of the late coloring maple hardwoods and oaks. Ashes, elms, sugar maples, etc are already pretty much bare around here. Link to comment Share on other sites More sharing options...
Chicago WX Posted October 18, 2012 Share Posted October 18, 2012 0.95" total at LAF. Third straight above normal month, 3.04" for October (normal: 2.89"). Link to comment Share on other sites More sharing options...
daddylonglegs Posted October 18, 2012 Share Posted October 18, 2012 La Crosse had no measurable rain... go figure... screw zone city. Wonder if this pattern will continue through winter? probably. Link to comment Share on other sites More sharing options...
trapperman Posted October 18, 2012 Share Posted October 18, 2012 La Crosse had no measurable rain... go figure... screw zone city. Wonder if this pattern will continue through winter? probably. Uh... not if you look at most of next week. You're sitting right on the warm front for 3-4 days straight. Link to comment Share on other sites More sharing options...
BowMeHunter Posted October 18, 2012 Share Posted October 18, 2012 Tropical., you should get some real growing lights. Bares should take note how a professional field is maintained. Link to comment Share on other sites More sharing options...
A-L-E-K Posted October 18, 2012 Share Posted October 18, 2012 what a sweet grow setup Link to comment Share on other sites More sharing options...
daddylonglegs Posted October 18, 2012 Share Posted October 18, 2012 Trapper- Yeah..i Just wish that heavy rain over Madison the past week would have shifted this way a little more... Its raining now, so every little bit helps.. Still need a real 2 to 3 inch soaker or a big monster blizzard What a day...45F and light rain... Day like this...wrong month.. Axl Rose...November Rain Link to comment Share on other sites More sharing options...
Geos Posted October 18, 2012 Share Posted October 18, 2012 DLL- looks like your doing pretty good with rainfall this month though according to this map! Link to comment Share on other sites More sharing options...
Hoosier Posted October 18, 2012 Share Posted October 18, 2012 Next week looks quite mild. Could have a few days well into the 70s around here if everything works out. Link to comment Share on other sites More sharing options...
beavis1729 Posted October 18, 2012 Share Posted October 18, 2012 Next week looks quite mild. Could have a few days well into the 70s around here if everything works out. Izzi had a nice discussion on this: BIG PATTERN CHANGE STILL ON TAP SUNDAY THROUGH THE FIRST HALF OF NEXT WEEK AS ANOTHER POWERHOUSE NORTHERN STREAM UPPER LOW CLOSES OFF OVER WESTERN NOAM RESULTING IN AMPLIFICATION OF A RIDGE DOWNSTREAM IN OUR NECK OF THE WOODS. SUNDAY WE SHOULD BE ABLE TO TACK ON ANOTHER 10F ONTO SATURDAY`S HIGHS WITH TEMPS RETURNING INTO THE MID TO UPPER 60S AS WARM AIR ADVECTION BEGINS TO REALLY GET GOING. THE PRECISE DETAILS OF MONDAY THROUGH WEDNESDAY WILL HINGE ON WHERE FRONT ENDS UP...WITH GFS AND ECMWF KEEPING IT GENERALLY NORTH OF THE CWA. HOWEVER...AT THIS DISTANCE IT LOOKS TO BE CLOSE ENOUGH TO REQUIRE AT LEAST SOME CHANCE POPS EACH DAY OF THE EXTENDED IN CASE IT DOES SLIP SOUTH...EVEN THOUGH THIS MAY GIVE THE UNREALISTIC IMPRESSION THAT IT WILL BE A WET PERIOD WHEN IN FACT THE MAJORITY OF THE TIME LOOKS DRY. SHOULD THE FRONT AND PRECIP HANG UP TO OUR NORTH THEN THE STAGE WOULD BE SET FOR TEMPERATURES TO SOAR TO UNSEASONABLY WARM LEVELS. BOTH THE LAST COUPLE RUNS OF THE GFS AND ECMWF HAVE BEEN ADVERTISING 850MB TEMPS IN THE 12-15C RANGE MON-WED WITH 925MB TEMPS BETWEEN 15-19C. LOOKING BACK AT SOME HISTORICAL COMPARISONS TO SIMILAR 850MB/925MB TEMPS WITH SIMILAR 500MB HEIGHTS (574-579DM) YIELDED HIGHS IN THE MID TO UPPER 70S THIS TIME OF YEAR. THE AVERAGE 850MB/925MB TEMPS FOR THE HANDFUL OF 80 DEGREE DAYS SINCE 1979 THE LAST HALF OF OCTOBER WERE AROUND 17C (850MB) AND 19-20C (925MB)...SO IF CURRENT FORECASTS VERIFY WE AREN`T TERRIBLY FAR FROM THAT. EVEN THE MEX GUIDANCE WHICH TENDS TO BE WEIGHTED MORE TOWARD CLIMO IN THE LONGER RANGE HAS TEMPS IN THE 70S. FINALLY...FOR THE LAST HALF OF OCTOBER...WHEN 850MB TEMPS ARE 11.5C OR WARMER HIGH TEMPS REACH AT LEAST 68F 90% OF THE TIME. GIVEN ALL THIS HAVE GONE WARMER THAN THE ALLBLEND INITIALIZATION TEMPS FOR HIGHS AND LOWS...BUT STILL SIGNIFICANTLY BELOW HOW WARM WE COULD POTENTIALLY BE DUE TO THE INHERENT UNCERTAINTIES IN LONGER RANGE FORECASTS...INCLUDING CLOUD COVER AND PRECIP IF THE FRONT IS CLOSER. Link to comment Share on other sites More sharing options...
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