Jump to content
  • Member Statistics

    17,586
    Total Members
    7,904
    Most Online
    LopezElliana
    Newest Member
    LopezElliana
    Joined

Feb 21-22 Snow/Sleet Storm Obs/Nowcasting/Weenie/Panic/Hallucinations


Ji

Recommended Posts

  • Replies 754
  • Created
  • Last Reply

Nope, 36 and just plain light rain/drizzle in wheaton. Not sure what to make of DCA's report. If it's accurate what does it mean that it's actually already SN mixing and not IP?

Yeah was wondering the same thing regarding the mixing. Fact that I haven't heard 1 ping, and have been through several moderate rain showers this evening, makes me wonder.

But absolutely no winter precip as of yet, here at least.

Link to comment
Share on other sites

mcd0119.gif

MESOSCALE DISCUSSION 0119

NWS STORM PREDICTION CENTER NORMAN OK

0533 PM CST MON FEB 21 2011

AREAS AFFECTED...PORTIONS CENTRAL/SERN OH...NRN WV...EXTREME SWRN

PA...NRN VA...NWRN THROUGH CENTRAL MD INCLUDING PANHANDLE...DC.

CONCERNING...WINTER MIXED PRECIPITATION

VALID 212333Z - 220430Z

EXISTING FREEZING RAIN SITUATION OVER PORTIONS CENTRAL/SRN OH AND

NRN PANHANDLE OF WV SHOULD SHIFT SLIGHTLY SWD. OVER CENTRAL-ERN

PARTS OF THIS CORRIDOR...FROM NERN WV ACROSS NRN MD...CURRENT AREAS

OF FREEZING RAIN ARE EXPECTED TO TRANSITION TO SNOW FROM N-S WITH

TIME...ALONG SRN LIMB OF REGIME COVERED IN SPC MESOSCALE DISCUSSION

118. MEANWHILE...HEAVIER PRECIP IS FCST TO SPREAD ACROSS THIS

REGION FROM WNW-ESE...AS RAIN CHANGES TO FREEZING RAIN...WITH RATES

.05-.1 INCH/HOUR...LOCALLY/BRIEFLY HEAVIER IN CORES.

23Z SFC MESOANALYSIS SHOWS WAVY FREEZING LINE FROM CENTRAL OH NEAR

CMH EWD NEAR HLG...ESEWD NEAR CBE...MRB...FDK...THEN NEWD PAST TO

RDG. THIS FREEZING LINE WILL SHIFT SWD THROUGH REMAINDER EVENING

PRIMARILY BECAUSE OF...

1. BOUNDARY LAYER CAA...AS SFC PRESSURE RISES NOW ANALYZED OVER

MID-ATLANTIC REGION REINFORCE LOWER-THETAE AIR MASS N OF FRONTAL

ZONE

2. SUBTLE DIABATIC SFC COOLING...AND ESPECIALLY

3. EVAPORATIVE/WET-BULB EFFECTS FROM PRECIP FALLING INTO LAYER OF

DRY ADVECTION N OF FRONT.

THESE FACTORS WILL FOSTER CHANGE FROM RAIN TO FREEZING RAIN IN AREAS

NOW S OF THAT LINE. MEANWHILE...TIME SERIES OF MODIFIED RUC

SOUNDINGS SUGGESTS SUPERFREEZING LAYER ABOVE SFC WILL COOL ON N SIDE

OF THIS CORRIDOR...LEADING TO PHASE TRANSITION FROM LIQUID TO SNOW

FROM N-S...WHILE STILL REMAINING WARM ENOUGH TO SUPPORT LIQUID

ELSEWHERE. MOISTURE TRANSPORT INTO THIS REGION SHOULD CONTINUE ON

NOSE OF LONG-FETCH/40-45 KT SWLY LLJ...WHILE SUPPORTIVE

ISENTROPIC/FRONTOGENETIC ASCENT MAXIMA SHIFT EWD ALONG THIS

CORRIDOR. STRONGEST FRONTOGENETIC FORCING SHOULD BE IN 750-850 MB

COLUMN...FROM WITHIN TO JUST BELOW BASE OF ELEVATED WARM LAYER...AND

NE OF EWD-MOVING SFC LOW. ON ERN END OF DISCUSSION AREA...OVER

NRN/CENTRAL MD...COOLING FROM 850 MB TO SFC MAY SHRINK WARM-LAYER

DEPTH ALOFT AND SUPPORT OCNL SLEET...HOWEVER...PRIND FREEZING RAIN

WILL BE PRIMARY PHASE OVER MOST OF THIS SWATH BEFORE CHANGE TO SNOW.

..EDWARDS.. 02/21/2011

ATTN...WFO...CTP...LWX...PBZ...RLX...ILN...

LAT...LON 40148317 40158252 40178069 39907941 39657770 39377656

38987644 38787666 38827752 39157894 39408053 39448166

39498294 39668354 40108335 40148317

Link to comment
Share on other sites

Hi 2/21: 39.1

7:00pm 2/21: 35.3, NNE 11-19 peak gust 24, DP 28, light rain

5:00pm 2/21: 38.2, NNE-11, DP 31, light rain and sleet

3:00pm 2/21: 38.7, N 11-14 peak gust 21, DP 32, Overcast

noon 2/21: 38.7, NW 3-7, DP 35, Overcast, Precip total= 0.04"

9:00am 2/21: 38.2, Wind N-9 peak gust 14, DP31.

8:30am 2/21: 38.3

Overnite Sun-Mon low 36.2, precip overnite 0.02"

Real-time temps, winds etc HERE

Link to comment
Share on other sites

AREA FORECAST DISCUSSION...UPDATED

NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC

654 PM EST MON FEB 21 2011

.SYNOPSIS...

-- Changed Discussion --A COLD FRONT OVER CENTRAL VIRGINIA WILL CONTINUE TO MOVE SOUTHWARD

SLOWLY THIS EVENING. LOW PRESSURE OVER THE MIDWEST WILL MOVE EAST

ALONG THE FRONT AND THROUGH THE MID-ATLANTIC STATES BY TUESDAY

MORNING. HIGH PRESSURE WILL BUILD INTO THE REGION MID-WEEK BEFORE

LOW PRESSURE IMPACTS THE MID-ATLANTIC STATES LATE THURSDAY AND

FRIDAY.-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...

-- Changed Discussion --PRIMARY CHG HAS BEEN TO ACCELERATE ONSET OF WINTRY PCPN. SLEET...

FRZG RAIN AND SNOW HAS SPREAD INTO FAR NRN TIER OF CTYS. WINTER

STORM WRNG START TIME WAS ADJUSTED FOR THIS NRN TIER...AND ICE WAS

INCLUDED IN FCST. OTHERWISE...HEADLINES RMN INTACT. SNOW XPCD TO

BCM MDT TO HVY AT TIMES TNGT AS MID-LVL JET BCMS STGR ACRS RGN.

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...