Jump to content
  • Member Statistics

    17,611
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

November 1-2 WY/CO/NE Snowstorm


boulderrr

Recommended Posts

  • Replies 75
  • Created
  • Last Reply

Is it just me or are actual temps today a good bit colder than forecast - 38.2 currently (noon) against a forecast hi of 49 for noon (max 51)?

http://www.wundergro...weekday=Tuesday

http://www.wundergro...ast?query=80124

Yep. And yesterday the highs for today were forecast to be in the mid 50s. Often the case, as the timing with these cold fronts can be tough to judge in advance. It's often faster than models show, though.

Link to comment
Share on other sites

12Z NAM a bit stronger than 6Z

6Z

nam_namer_030_precip_p24.gif

12Z

nam_namer_024_precip_p24.gif

Really smelled like snow this morning after the initial FROPA... now it's crystal clear and snow is the last thing you'd expect. Hope the NAM verifies! If the sun stays out much longer we'll have a little bit of work to do to change precip to snow.

Last week's storm brought down 100% of our front yard leaves, and our backyard leaves (different kind of course) are still largely green. 50 feet, two seasons! Weird.

Link to comment
Share on other sites

Really smelled like snow this morning after the initial FROPA... now it's crystal clear and snow is the last thing you'd expect. Hope the NAM verifies! If the sun stays out much longer we'll have a little bit of work to do to change precip to snow.

Last week's storm brought down 100% of our front yard leaves, and our backyard leaves (different kind of course) are still largely green. 50 feet, two seasons! Weird.

Still a pretty thick stratus layer over Boulder with the temperature at ~39F.

bfc-0.jpg

Link to comment
Share on other sites

Really smelled like snow this morning after the initial FROPA... now it's crystal clear and snow is the last thing you'd expect. Hope the NAM verifies! If the sun stays out much longer we'll have a little bit of work to do to change precip to snow.

Last week's storm brought down 100% of our front yard leaves, and our backyard leaves (different kind of course) are still largely green. 50 feet, two seasons! Weird.

Funny how different things can be across the urban corridor. We have been socked in with clouds all day in Boulder. They've actually thinned out a little since the morning but not a minute of sunshine.

Yeah what he said. ^^^^ :lol:

Link to comment
Share on other sites

HPC Day 1 Snow Accumulation Probabilities

>4 Inches

day1_psnow_gt_04.gif

>8 Inches

day1_psnow_gt_08.gif

>12 Inches

day1_psnow_gt_12.gif

PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION

NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD

412 PM EDT TUE NOV 01 2011

VALID 00Z WED NOV 02 2011 - 00Z SAT NOV 05 2011

DAY 1...

...WYOMING...COLORADO AND WESTERN NEBRASKA...

A SPLIT FLOW UPPER TROUGH OVER THE NRN INTER-MOUNTAIN WEST EARLY TUES IS QUICKLY TRANSITIONING TOWARD A VERY ACTIVE SRN BRANCH SHORT WAVE TROUGH... AS UPPER DYNAMICS INTENSIFY THROUGH THE CENTRAL GRT BASIN. THIS POTENT AND ACTIVE FEATURE WILL ROLL THROUGH THE CENTRAL/SRN ROCKIES BEFORE EJECTING OUT INTO THE CENTRAL PLAINS ON WED. IN FACT... MODEL GUIDANCE CONTINUES TO ADVERTISE POSSIBLE MID-LEVEL LOW CLOSING OFF EARLY WED AS IT PASSES THROUGH CENTRAL/SRN CO. AS THIS OCCURS ALOFT... A STRONG POLAR COLD FRONT WILL CONTINUE TO DROP DOWN THE FRONT RANGE OF THE ROCKIES ALLOWING A MASSIVE AREA OF SURFACE HIGH PRESSURE TO BUILD IN BEHIND. THIS SHOULD SET UP AN IDEAL PATTERN FOR ANOTHER WIDESPREAD UPSLOPE/OROGRAPHIC HVY SNOWFALL EVENT ACROSS SRN WY/MOST OF CO INTO THE FRONT RANGE/CENTRAL HIGH PLAINS FROM LATE TUES THROUGH MOST OF WED. HPC CONTINUES TO REALLY PREFER A COMBINATION OF THE OPERATIONAL ECMWF AND GFS MASS FIELDS THROUGHOUT THE FCST... WHICH INCLUDES THE CRITICAL QPF AND THERMAL PROFILES. THE HVY SNOW ON WED SHIFTS TO CO AND SRN WY/WRN NE... AS DIGGING SRN STREAM TROUGH W/ SOLID JET DYNAMICS AND MID-LEVEL LOW TRACKS ACROSS CO ENHANCING THE VERTICAL LIFT AND ERLY/ENERLY UPSLOPE COMPONENT. BOTH THE ECMWF AND GFS SHOW A WIDENING ZONE OF 850-650MB FRONTOGENESIS LAYER FOR POSSIBLE BANDING SNOW AND ENHANCED SNOWFALL RATES EARLY WED... SOLID AXIS OVER CO FROM 03Z/2 TO 09Z/2... BEFORE EXPANDING DEFORMATION ZONE BEGINS TO SHIFT INTO THE CENTRAL PLAINS. EXPECT SIGNIFICANT SNOWFALL ACCUMULATIONS IN THE CO ROCKIES INTO THE SERN TERRAIN OF WY AND SPREADING DOWN THE FOOTHILLS INTO THE DENVER METRO AREA.

Link to comment
Share on other sites

MESOSCALE DISCUSSION 2283

NWS STORM PREDICTION CENTER NORMAN OK

0813 PM CDT TUE NOV 01 2011

AREAS AFFECTED...ROCKIES OF SRN WY AND NRN/CNTRL CO...AS WELL AS THE

ADJACENT HIGH PLAINS

CONCERNING...BLIZZARD

VALID 020113Z - 020615Z

BANDS OF HEAVY SNOW WITH RATES TO 2 IN/HR WILL DEVELOP FROM N TO S

OVER THE ROCKIES OF SRN WY AND NRN/CNTRL CO...AS WELL THE ADJACENT

HIGH PLAINS DURING THE EVENING AND OVERNIGHT HOURS. BLIZZARD

CONDITIONS WILL LIKELY DEVELOP OVER THE CO HIGH PLAINS...PRIMARILY

AFTER 06Z.

WATER VAPOR LOOP DEPICTS A POTENT MID/UPPER-LEVEL IMPULSE WITHIN THE

BASE OF A LONGWAVE TROUGH OVER THE WRN CONUS...WITH AN ATTENDANT

250-MB JET STREAK FEATURING SWLY CORE WINDS AROUND 120 KT OVER CO.

STRONG ASCENT WITHIN THE LEFT-EXIT REGION OF THIS FEATURE AUGMENTED

BY DOWNSTREAM DCVA...COUPLED WITH A NNWWD-SLOPING BAROCLINIC ZONE

WILL INDUCE A STRENGTHENING FRONTOGENETIC CIRCULATION OVER THE

ROCKIES AND ADJACENT HIGH PLAINS. ATTENDANT LOW-LEVEL ASCENT WILL

ALLOW WSW-ENE-ORIENTED SNOW BANDS TO DEVELOP SWD DURING THE NEXT

SEVERAL HOURS...AIDED BY INCREASING SLANTWISE CONVECTION. SNOWFALL

RATES TO 2 IN/HR WILL BE LIKELY WITHIN THESE SNOW BANDS...HIGHEST

ALONG THE IMMEDIATE FRONT RANGE AND ADJACENT FOOTHILLS. AN ISOLATED

LIGHTNING STRIKE OR TWO WILL BE POSSIBLE WITH THE HEAVIEST SNOW.

MEANWHILE...THE LOW-LEVEL PRESSURE PATTERN WILL SUPPORT

STRENGTHENING ELY/UPSLOPE FLOW AS AN ISALLOBARIC RESPONSE TO SFC

PRESSURE RISES TO THE E/NE. IN TURN...ADIABATIC COOLING AND AN

ASSOCIATED MESO-RIDGE AND BARRIER JET WILL DEVELOP JUST EAST OF THE

FRONT RANGE...WHICH IS ALREADY BEING MANIFESTED IN THE PRONOUNCED

NLY SURGE AND PRESSURE RISES OBSERVED INVOF DENVER. THIS WILL ALLOW

SUBFREEZING AIR IN SERN WY TO QUICKLY SURGE SWD JUST EAST OF THE

FRONT RANGE AND SUPPORT SNOW...WHILE ALSO STRENGTHENING ISENTROPIC

ASCENT FOR PARCELS WITH TRAJECTORIES EMANATING FROM THE EAST. THIS

WILL ENHANCE SNOWFALL RATES FROM FORT COLLINS TO DENVER AFTER 05Z.

FARTHER EAST OVER THE HIGH PLAINS OF NERN/E-CNTRL CO...SNOWFALL

RATES MAY ONLY REACH 1 IN/HR. HOWEVER...THE AFOREMENTIONED

MESO-RIDGE WILL TIGHTEN THE LOW-LEVEL PRESSURE GRADIENT SUFFICIENTLY

TO PRODUCE NLY TO NELY WINDS TO 35 MPH WITH FREQUENTLY HIGHER GUSTS.

THESE WINDS WILL COMBINE WITH BURSTS OF HEAVIER SNOW TO GENERATE

BLIZZARD CONDITIONS...PREDOMINANTLY AFTER 06Z. THE SNOW AND BLIZZARD

CONDITIONS WILL LIKELY PERSIST THROUGH MUCH OF THE NIGHT...WHILE

TAPERING OFF FROM N TO S WEDNESDAY MORNING.

..COHEN.. 11/02/2011

Link to comment
Share on other sites

First few flakes just starting to mix in here just west of Englewood. I drive everyone at work crazy with my enjoyment of snow :)

Never know when to hide it vs. just celebrate my inner weather geek. Then again, people at work do ask me what I think will happen. I should tell them something like "cows will fall from the sky..." :rolleyes:

Almost ripping here, about 4 miles north of KAPA. 1" in the past hour, changed from rain to snow about 9:10. From the NWS discussions wouldn't be surprised to hear some thunder here the next hour or two as the front and lift sink southward.

Enjoy! Off to bed, gotta get up early and shovel. :snowman:

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...