January 14th - 15th Plains/MW/OV/GL Clipper OBS, Please Post Last Minute Forecast and OBS Options

[Gilbertfly]

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
158 PM EST TUE JAN 10 2012

VALID 12Z FRI JAN 13 2012 - 12Z TUE JAN 17 2012


MADE ONLY COSMETIC CHANGES TO THE UPDATE PACKAGE FOR THE FINAL
ISSUANCE. THE 12Z/10 GUIDANCE OFFERED NO COMPELLING REASONS TO
STEM THE COURSE OF THE MEDIUM RANGE FORECAST. IN FACT...THE
CHOICE TO NOT DEPICT A VIGOROUS WAVE OVER THE EASTERN UNITED
STATES WAS BOLSTERED BY THE DROPPING OF THAT FEATURE ON THE LATEST
DETERMINISTIC ECMWF AND GEM GLOBAL. IT APPEARS THE CLIPPER
TRAVERSING THE MIDWEST AND MID ATLANTIC STATES DAYS 4 AND 5 MAY BE
ENERGETIC ENOUGH TO PAINT A SWATH OF FLUFFY SNOW ACROSS THESE
REGIONS.

i am a clipper thread. . .my titles may need some help from a moderator. . .thank you

This post has been edited by Gilbertfly: Jan 14 2012, 10:15 AM

[Gilbertfly]

LOT...

NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
320 PM CST TUE JAN 10 2012

ANOTHER LOBE OF VORTICITY IS POISED TO PIVOT ALONG THE BACK EDGE OF
THE 500MB TROUGH FRI EVE...AS A CLIPPER SYSTEM QUICKLY SLIDES
SOUTHEAST TOWARDS THE WESTERN GREAT LAKES SAT.

TEMPS FRI WILL STRUGGLE TO WARM ABOVE THE MID/UPR TEENS.

SATURDAY THROUGH MONDAY...
AS PREVIOUSLY MENTIONED A CLIPPER SYSTEM WILL TRAVERSE THE WESTERN
GREAT LAKES REGION EARLY SAT...WHICH COULD BRING SOME LIGHT
SNOW/FLURRIES TO THE REGION. FOR NOW HAVE MAINTAINED A DRY
FORECAST...AS THIS SYSTEM HAS VERY MINIMAL MOISTURE TO WORK WITH AND
IS SLIDING INTO ANTI-CYCLONIC FLOW WITH A BROAD SFC RIDGE ACROSS THE
MISSOURI VALLEY AND OZARKS REGION SAT.

[Gilbertfly]

i am a clipper thread. . .my titles may need some help from a moderator. . .thank you

thanks!!!!!

[Gilbertfly]

Clipper rollin' on in the 00Z GFS. . .

[Gilbertfly]

LOT...

NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
604 AM CST WED JAN 11 2012

NEXT CLIPPER PROGGED TO RACE SOUTHEASTWARD ACROSS THE MIDWEST
SATURDAY. DESPITE LIMITED MOISTURE...QUITE PLAUSIBLE THAT THERE WILL
BE A BAND OF LIGHTLY ACCUMULATING SNOW TO THE LEFT OF THE TRACK OF
THIS SYSTEM. MODEL QPF IS UNIMPRESSIVE...BUT NOT UNCOMMON FOR MODELS
TO HAVE TO PLAY CATCH UP WITH CLIPPERS. GIVEN UNCERTAINTIES WITH
RESPECT TO QPF AND TRACK HAVE ONLY INCREASED POPS INTO THE LOW END
CHANCE RANGE FOR NOW.

[Gilbertfly]

12Z NAM...

[Gilbertfly]

per monger's post. . .clipper showing up on the HPC's cluster/track map. . .



and D3 probs...

[Gilbertfly]

HPC. . .

PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
346 PM EST WED JAN 11 2012

...NORTHERN PLAINS INTO THE MIDWEST...
BACKSIDE ENERGY AND ALBERTA CLIPPER-TYPE SYSTEM ARE EXPECTED TO
ADVANCE SOUTHEASTWARD WITH PACIFIC JET-AXIS AND LEFT EXIT REGION
DYNAMICS ALLOWING FOR MID-LEVEL CYCLONIC FLOW TO SPREAD LIGHT
MID-LEVEL WARM ADVECTION SNOWFALLS ACROSS THE DAKOTAS AND THE
MID-MS VALLEY BY THE END OF DAY 3. THE 12Z GUIDANCE REMAINS VERY
WEAK WITH THE SURFACE WAVE...AND THEREFORE...LIMITED IN ITS
ABILITY TO PRODUCE MORE THAN LIGHT SNOW ACCUMULATIONS ACROSS
PORTIONS OF SWRN WI...ERN IA AND CENTRAL/SRN IL.

[Gilbertfly]

LOT...

NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
253 PM CST WED JAN 11 2012

THE CLOSED CIRCULATION ALOFT THAT WILL BRING THE BLAST OF WINTER
WEATHER WILL MOVE ACROSS THE NORTHEASTERN STATES BY THE AFTERNOON ON
FRIDAY. IN THE WAKE OF THIS SYSTEM WILL BE WEAK SURFACE RIDGING THAT
WILL FLIP WINDS BACK TO THE SOUTHWEST AND ADVECT IN A LITTLE WARMER
AIR FROM THE COLDER AIRMASS THAT WAS DUMPED ACROSS THE REGION. WHILE
STILL CHILLY...HIGHS WILL MANAGE TO GET WITHIN REACH OF NORMAL FOR
THIS TIME OF YEAR ON SATURDAY...WITH GENERALLY LOWER 30S EXPECTED
SOUTH OF I-80 AND TEMPS JUST BELOW NORMAL TO THE NORTH. INTO THE
EVENING ANOTHER CLIPPER WILL DIVE OUT OF THE NORTHERN PLAINS AND
ACROSS THE CWA THROUGH EARLY SUNDAY MORNING. THERE IS STILL A
LITTLE UNCERTAINTY WITH RESPECT TO THE TRACK OF THE CLIPPER MOVING
THROUGH...AS ALL GUIDANCE /ECMWF - GEMNH - GFS/ HAVE TRENDED A
LITTLE FURTHER SOUTH OVER THE LAST FEW RUNS...SO CONFIDENCE IS NOT
THE HIGHEST WITH THE LIKELIHOOD ON WHERE THE LOW WILL TRACK.
REGARDLESS...THE SYSTEM WILL MOVE THROUGH PRETTY QUICKLY AND ONLY
IMPACT THE CWA IN THE AFTERNOON TO EVENING HOURS WITH A LIGHT
DUSTING OF SNOW. DUE TO THE UNCERTAINTY...WILL MAINTAIN ONLY THE
MENTION OF CHANCE POPS AT THIS TIME BUT LEAN TOWARDS A LATER POINT
IN THE DAY FOR IT TO MOVE THROUGH. CONDITIONS WILL REMAIN NEAR TO
BELOW NORMAL TO CLOSE OUT THE WEEKEND.

[ohiobuckeye45]

looked healthy last night...no so much today. But theres way to much skewing its track/ intensity right now to call anything

[CentralIllinois]

00Z NAM a great hit for N/C IL and IN
hr 72


hr 78

[WeatherMonger]

00Z NAM a great hit for N/C IL

Was just getting ready to post. Will be interesting, actually starting to feel a bit like Decem....errr January

[xigris14]

Was just getting ready to post. Will be interesting, actually starting to feel a bit like Decem....errr January

I want a little taste of that moisture in St Louis, its close and hopefully it can swing a bit south and west.

[WeatherMonger]

36 hour QPF at 84. There is overlap From Eastern IL border East, but everything West and North is the clipper

[CentralIllinois]

36 hour QPF at 84. There is overlap From Eastern IL border East, but everything West and North is the clipper

not bad looks like it could be a decent event on top of what we get tomorrow and early friday

[WeatherMonger]

Put me just over 1 1/2"

120114/2000Z 68 18010KT 29.3F SNOW 15:1| 0.4|| 0.00|| 0.00|| 0.028 15:1| 0.4|| 0.00|| 0.00|| 0.03 100| 0| 0
120114/2100Z 69 20010KT 30.2F SNOW 15:1| 0.7|| 0.00|| 0.00|| 0.047 15:1| 1.1|| 0.00|| 0.00|| 0.07 100| 0| 0
120114/2200Z 70 21010KT 31.3F SNOW 17:1| 0.4|| 0.00|| 0.00|| 0.024 16:1| 1.5|| 0.00|| 0.00|| 0.10 100| 0| 0
120114/2300Z 71 23009KT 32.0F SNOW 12:1| 0.1|| 0.00|| 0.00|| 0.008 15:1| 1.6|| 0.00|| 0.00|| 0.11 100| 0| 0
120115/0000Z 72 25010KT 32.5F 0:1| 0.0|| 0.00|| 0.00|| 0.000 15:1| 1.6|| 0.00|| 0.00|| 0.11 0| 0| 0

[WeatherMonger]

0Z GFS not so much. 48 hour QPF at hour 96, maybe a bit of overlap in OH area but not much

[WeatherMonger]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
319 AM CST THU JAN 12 2012

LONG TERM...SATURDAY THROUGH WEDNESDAY
QUICKLY ON THE HEELS OF THIS SYSTEM...AN ALBERTA CLIPPER WILL DIVE
DOWN THE BACK SIDE OF THE TROUGH ON SATURDAY. 00Z MODELS ARE
COMING INTO BETTER AGREEMENT ON THE TRACK WHICH WOULD TARGET
CENTRAL IL...AND HAVE RAISED POPS INTO HIGH CHC CATEGORY FOR THE
AFTERNOON. LOOKS TO BE A STRONGLY FORCED BUT LIMITED MOISTURE
CLIPPER. CURRENT INDICATIONS SHOW AN INCH OR TWO OF ACCUMULATION
WOULD BE POSSIBLE.

[Gilbertfly]

LOT...

NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
543 AM CST THU JAN 12 2012

BY SATURDAY A FAST MOVING CLIPPER IS PROGGED TO ZIP SOUTHEASTWARD
ACROSS THE MIDWEST. NOT AN OVERLY STRONG SYSTEM AND WILL BE MOISTURE
STARVED...BUT WITH PERSISTENT WARM AIR ADVECTION MIGHT BE ABLE TO
LAY DOWN A BAND OF AN INCH OR SO OF SNOW. MODELS GENERALLY TRACK
SURFACE LOW FROM NORTHERN IOWA INTO SOUTHERN ILLINOIS WHICH WOULD
FAVOR OUR WESTERN CWA FOR HIGHEST CHANCES OF SNOW. HAVE TRENDED POPS
UP IN THE GRIDS AGAIN...WELL ABOVE MOS GUIDANCE AND MORE IN LINE
WITH HPC QPF FORECAST OF GREATER THAN A TENTH OF AN INCH. CLIPPER
SHOULD BE OUT OF THE AREA BY LATER SATURDAY EVENING WITH CLOUDS
PROBABLY STICKING AROUND AND KEEPING TEMPS SOMEWHAT IN CHECK
SATURDAY NIGHT.

[WeatherMonger]

Clipper showing up on the WRF-NMM. Looked week and NE on both the NAM and GFS this morning