Second Blizzard Warning This Year !!
Another example of how forecasters can become model dependent is the blizzard warning that was issued this morning. In the quick weather outlook I inserted at the end of Monday’s global warming post, I said that we will see snow in the great plains today while everyone else was calling for rain. The reason everyone was calling for rain instead of snow is because NAM said that no snow was in the future for the great plains, and people tend to favor NAM for snowfall forecasts out a few days, especially since certain fields are integrated into the NDFD. Below is our HAMmodel NAM snowdepth product animation from Monday. Recall that this product run has forecasts of 3 hour intervals out to 84 hours, and this animation is from 12z Monday morning, and the last cycle F84 is valid 00z Friday.
|NAM Snowdepth Product Animation 12z Mon – 00z Friday||GFS Snowdepth Product Animation 12z Mon – 00z Tuesday|
Review this post and associated references for a better understanding of the product. Notice how the snowfall in the northeast over the last few days was picked up by NAM, as well as predicted snowfall in the Rockies and the Pacific northwest; however, nothing was forecast for the Nebraska region (my initial thoughts), to the now extended snowfall area into Kansas. This is not unusual for NAM in the great plains this time of year because of the processes that will be associated in generating the snowfall.
Just for grins and giggles I also included the GFS snowdepth product above beginning at 12z Monday which runs at 6 hour intervals out 180 hours through 00z next Tuesday morning. Do you notice a difference in predicted snowdepth for the same timeframe as NAM? Watch the next few days to see how things turn out!
Below are two of our HAMweather products from this morning.
At left is our HWwarnings product that displays the current advisories for the Nebraska, Kansas, Colorado region currently expecting snow. It is always best to view the product live, but for now a general key is: blizzard warning (red), winter storm warning (magenta/pink looking), winter weather advisory (purple), and winter storm watch (bluish color beside purple =]), with the associated wind advisories surrounding the warnings.
The image at right is our HAMrad II product overlain with frontal boundaries, isobars, and warnings. Notice how the warnings are depicted on the ‘left’ side of the strong area of lower pressure that is currently propagating east away from the rockies, with the strongly amplified trough I mentioned on Monday. Snow will begin to fall as the system moves, and strong northerly winds intensify transferring cooler air into the region. Additionally, an elongated precipitation shield will extend east and south from the system over the next few days adding to the previous rainfall totals as it progresses.
The current blizzard warning issued at 4.23am CDT is below.
Issue Date: 423 AM CDT WED OCT 22 2008
Expiration: 700 PM CDT THU OCT 23 2008
…AN ABRUPT CHANGE TO WINTER IS HEADED FOR THE TRI-STATE AREA TONIGHT AND THURSDAY…
A STRONG LOW PRESSURE SYSTEM WILL MOVE OUT OF THE ROCKIES AND INTO THE TRI-STATE AREA TONIGHT. LIGHT SNOW ALREADY OCCURRING IN EASTERN COLORADO IS EXPECTED TO SLOWLY SPREAD EAST INTO NORTHWEST KANSAS AND EXTREME SOUTHWEST NEBRASKA THIS AFTERNOON AND THIS EVENING. SNOW WILL BECOME HEAVY AT TIMES TONIGHT AND STRONG WINDS WILL CAUSE CONSIDERABLE BLOWING AND DRIFTING SNOW. TRAVEL WILL BECOME HAZARDOUS WITH WHITEOUT CONDITIONS. THE SNOW WILL CONTINUE ON THURSDAY BEFORE GRADUALLY DIMINISHING THURSDAY EVENING.
KSZ001>004-013>016-027>029-NEZ079>081-221800-/O.NEW.KGLD.BZ.W.0003.081023T0000Z-081024T0000Z/CHEYENNE KS-RAWLINS-DECATUR-NORTON-SHERMAN-THOMAS-SHERIDAN-GRAHAM-WALLACE-LOGAN-GOVE-DUNDY-HITCHCOCK-RED WILLOW-INCLUDING THE CITIES OF…ST. FRANCIS…ATWOOD…OBERLIN…NORTON…GOODLAND…COLBY…HOXIE…HILL CITY…SHARON SPRINGS…
321 AM MDT WED OCT 22 2008 /421 AM CDT WED OCT 22 2008/
…BLIZZARD WARNING IN EFFECT FROM 6 PM MDT /7 PM CDT/ THIS EVENING TO 6 PM MDT /7 PM CDT/ THURSDAY…
THE NATIONAL WEATHER SERVICE IN GOODLAND HAS ISSUED A BLIZZARD WARNING…WHICH IS IN EFFECT FROM 6 PM MDT /7 PM CDT/ THIS EVENING TO 6 PM MDT /7 PM CDT/ THURSDAY.
SNOW WILL GRADUALLY SPREAD EAST OF THE COLORADO STATE LINE THIS AFTERNOON AND EVENING AND BECOME HEAVY AT TIMES OVERNIGHT. SNOW AMOUNTS RANGING FROM 3 TO 4 INCHES IN THE GOODLAND AREA TO 4 TO 6 INCHES IN THE HOXIE AREA ARE POSSIBLE. HEAVIER SNOWFALL RANGING
FROM 6 TO 12 INCHES IS POSSIBLE FROM MCCOOK TO HILL CITY BEFORE THE STORM TAPERS OFF THURSDAY EVENING. NORTH WIND AT 30 TO 35 MPH WITH GUSTS TO 45 MPH WILL CREATE WIDESPREAD BLOWING AND DRIFTING SNOW PRODUCING DANGEROUS BLIZZARD CONDITIONS.
A BLIZZARD WARNING MEANS STRONG WINDS AND FALLING OR BLOWING SNOW WILL PRODUCE WHITEOUT CONDITIONS AT TIMES…WITH TRAVEL BECOMING DIFFICULT OR IMPOSSIBLE. MONITOR LOCAL FORECASTS BEFORE DECIDING TO VENTURE OUTSIDE.
IF YOU MUST TRAVEL AND YOU BECOME STRANDED… STAY WITH YOUR VEHICLE UNTIL HELP ARRIVES.
The current winter storm warning as of 3.47am CDT.
WINTER STORM WARNING
Issue Date: 347 AM CDT WED OCT 22 2008
Expiration: 100 AM CDT FRI OCT 24 2008
…THE FIRST WINTER STORM OF THE SEASON IS POSSIBLE WEDNESDAY MORNING THROUGH THURSDAY EVENING ACROSS WESTERN AND NORTH CENTRAL NEBRASKA…
THE POTENTIAL EXISTS FOR A MAJOR WINTER STORM TO IMPACT WESTERN AND NORTH CENTRAL NEBRASKA WEDNESDAY AND THURSDAY. AN INTENSE… UPPER LEVEL LOW…WILL DEVELOP ACROSS WESTERN AND NORTH CENTRAL NEBRASKA OVERNIGHT TONIGHT. AS THIS FEATURE TRACKS SLOWLY EAST…
RAIN IS LIKELY WITH A CHANGEOVER TO SNOW POSSIBLE BY WEDNESDAY MORNING. IN ADDITION TO HEAVY SNOW…STRONG WINDS WITH GUSTS TO 50 MPH WILL BE POSSIBLE BEHIND THE COLD FRONT. THE COMBINATION OF HEAVY SNOW AND WINDS MAY PRODUCE NEAR WHITEOUT CONDITIONS.
INCLUDING THE CITIES OF… THEDFORD… DUNNING… TAYLOR… TRYON… STAPLETON… BROKENBOW… OGALLALA… GRANT… NORTH PLATTE… IMPERIAL… HAYES CENTER… CURTIS… EUSTIS
346 AM CDT WED OCT 22 2008 /246 AM MDT WED OCT 22 2008/
…WINTER STORM WARNING IN EFFECT FROM 7 PM CDT /6 PM MDT/ THIS EVENING TO 1 AM CDT /MIDNIGHT MDT/ FRIDAY…
THE NATIONAL WEATHER SERVICE IN NORTH PLATTE HAS ISSUED A WINTER STORM WARNING FOR HEAVY SNOW AND BLOWING SNOW…WHICH IS IN EFFECT FROM 7 PM CDT /6 PM MDT/ THIS EVENING TO 1 AM CDT /MIDNIGHT MDT/ FRIDAY. THE WINTER STORM WATCH IS NO LONGER IN EFFECT.
RAIN IS EXPECTED TO GRADUALLY CHANGEOVER TO SNOW LATE THIS AFTERNOON AND EVENING. BY FRIDAY MORNING…TOTAL SNOW ACCUMULATIONS OF 5 TO 9 INCHES…WITH LOCALLY HIGHER AMOUNTS ARE EXPECTED…WITH THE HEAVIEST AMOUNTS OVER FRONTIER…SOUTHEASTERN
LINCOLN AND SOUTHERN CUSTER COUNTY.
THE SNOW WILL COMBINE WITH STRONG NORTHERLY WINDS PRODUCING CONSIDERABLE BLOWING SNOW. VISIBILITIES WILL BE REDUCED AND TRAVEL WILL BECOME VERY HAZARDOUS OR IMPOSSIBLE. IF YOU MUST TRAVEL TONIGHT…PACK A WINTER SURVIVAL KIT.
RANCHERS…SHOULD TAKE MEASURES TO PROTECT YOUNG LIVESTOCK FROM THE COLD AND SNOWY CONDITIONS.
I have been asked if I will explain the IPCC’s Fourth Assessment Report since I posted the global warming blog on Monday. I have no problem doing so, therefore in addition to the future blogs on tropical systems, snowfall, tornadoes, and rainfall I will break down the IPCC’s latest report into multiple sections over the next month or so for you.
As always stay tuned to your favorite weather outlet, stay informed, and stay safe!