[spotters-illianaskywarn] Fwd: NOAA's National Weather Service SPC Mesoscale Discussion Update
- From: Keith Reedy <keithreedy@xxxxxxxxxxxx>
- To: "spotters-illianaskywarn@xxxxxxxxxxxxx" <spotters-illianaskywarn@xxxxxxxxxxxxx>
- Date: Sat, 12 Jan 2013 19:55:51 -0500
Keith Reedy
keithreedy@xxxxxxxxxxxx
Begin forwarded message:
> From: GovDelivery Weather Updates <weatherupdates@xxxxxxxxxxxxxxxxxxxxxx>
> Subject: NOAA's National Weather Service SPC Mesoscale Discussion Update
> Date: January 12, 2013 7:21:52 PM EST
> To: keithreedy@xxxxxxxxxxxx
> Reply-To: GovDelivery Weather Updates <weatherupdates@xxxxxxxxxxxxxxxxxxxxxx>
>
>
>
> You are subscribed to SPC Mesoscale Discussion for NOAA's National Weather
> Service.
> GovDelivery provides this service using unaltered NOAA/NWS products.
>
>
> SPC MD 17
> 01/12/2013 07:18 PM EST
>
> MD 0017 CONCERNING WINTER MIXED PRECIPITATION FOR NWRN
> INDIANA...NRN/CNTRL/W-CNTRL IL...PARTS OF E-CNTRL/SERN/S-CNTRL MO
>
>
> MESOSCALE DISCUSSION 0017
> NWS STORM PREDICTION CENTER NORMAN OK
> 0617 PM CST SAT JAN 12 2013
>
> AREAS AFFECTED...NWRN INDIANA...NRN/CNTRL/W-CNTRL IL...PARTS OF
> E-CNTRL/SERN/S-CNTRL MO
>
> CONCERNING...WINTER MIXED PRECIPITATION
>
> VALID 130017Z - 130615Z
>
> SUMMARY...WINTER MIXED PRECIPITATION WILL INCREASE IN COVERAGE AND
> INTENSITY THIS EVENING. THIS WILL INCLUDE THE THREAT FOR FREEZING
> RAIN WITH RATES OF 0.05 TO 0.10 IN/HR...WITH LOCALLY HIGHER RATES
> ALSO POSSIBLE. FREEZING RAIN WILL BECOME INCREASINGLY LIKELY IN THE
> CHICAGO AND ST. LOUIS AREAS AFTER 04Z.
>
> DISCUSSION...A LARGE SHIELD OF CONVECTIVE-DEBRIS-RELATED
> PRECIPITATION WITHIN A WARM CONVEYOR BELT WILL CONTINUE TO
> OVERSPREAD THE AREA THIS EVENING. THIS ACTIVITY SHOULD PERSIST THE
> OVERNIGHT HOURS AS ELEVATED WARM ADVECTION OCCURS THROUGH THE
> NIGHT...WITH A TENDENCY FOR HIGHER PRECIPITATION RATES TO SHIFT NEWD
> IN TANDEM WITH THE STRONGER ASCENT.
>
> AS SUBFREEZING SFC-LAYER TEMPERATURES UNDERCUT THE ELEVATED WARM
> ADVECTION...THE LEADING EDGE OF WINTER MIXED PRECIPITATION WILL
> ADVANCE ESEWD ACROSS THE REGION. IMMEDIATELY BEHIND THIS LEADING
> EDGE...A 40-70-MILE WIDE CORRIDOR OF POTENTIAL FREEZING RAIN WILL BE
> ASSOCIATED WITH LIQUID-EQUIVALENT RATES OF 0.05-0.10 IN/HR. LOCALLY
> HIGHER RATES MAY OCCUR OWING TO A MODEST CONVECTIVE ENHANCEMENT
> ASSOCIATED WITH NARROW ELEVATED CAPE PROFILES. THE FREEZING-RAIN
> CORRIDOR WILL LIKELY MOVE INTO NWRN INDIANA BY 07Z.
>
> SENSIBLE HEAT FLUXES ASSOCIATED WITH PREVIOUSLY FALLEN LIQUID MAY
> INITIALLY DELAY THE ONSET OF ICING ON MANY SURFACES...ASIDE FROM
> ELEVATED/METAL SURFACES. REGARDLESS...OBSERVATIONS UPSTREAM ACROSS
> CNTRL MO INTO NERN OK INDICATE PERSISTENT FREEZING RAIN
> OCCURRING...AND SFC ICING WILL BE LIKELY.
>
> TO THE WNW OF THE FREEZING-RAIN CORRIDOR...DEEPER COLD AIR WILL
> LIMIT/PRECLUDE MELTING OF DESCENDING HYDROMETERS AND SUPPORT SLEET
> AND LIGHT TO OCCASIONALLY MODERATE SNOW. REMAINING PRECIPITATION
> WILL PROGRESSIVELY TRANSITION TO SLEET/SNOW FROM WNW TO ESE DURING
> THE OVERNIGHT HOURS...ESPECIALLY ACROSS NRN IL. PRECIPITATION RATES
> ARE EXPECTED TO DECREASE AREA-WIDE BY 09Z AS STRONGER FORCING FOR
> ASCENT SHIFTS NE OF THE AREA.
>
> PLEASE REFERENCE MCD 16 FOR ADDITIONAL DETAILS REGARDING ONGOING
> WINTER MIXED PRECIPITATION ACROSS NERN OK...SERN KS...CNTRL MO...AND
> W-CNTRL IL.
>
> ..COHEN.. 01/13/2013
>
> ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
>
> ATTN...WFO...PAH...LOT...ILX...LSX...DVN...SGF...
>
> LAT...LON 42428783 41838762 41628732 41668710 41638697 41398697
> 41168716 40538755 39478833 38798905 37649004 36759171
> 36519342 36659386 36919364 37599270 38429166 39459025
> 40098976 40779025 41449012 41868981 42368904 42428783
>
> Read more
> SPC MD 16
> 01/12/2013 07:00 PM EST
>
> MD 0016 CONCERNING WINTER MIXED PRECIPITATION FOR NERN OK...SERN KS...CNTRL
> MO...W-CNTRL IL
>
>
> MESOSCALE DISCUSSION 0016
> NWS STORM PREDICTION CENTER NORMAN OK
> 0345 PM CST SAT JAN 12 2013
>
> AREAS AFFECTED...NERN OK...SERN KS...CNTRL MO...W-CNTRL IL
>
> CONCERNING...WINTER MIXED PRECIPITATION
>
> VALID 122145Z - 130315Z
>
> SUMMARY...WINTER MIXED PRECIPITATION IS EXPECTED TO INCREASE LATE
> THIS AFTERNOON AND EVENING FROM NERN OK NEWD INTO W-CNTRL IL AS
> HEAVIER PRECIPITATION MOVES IN FROM THE SSW. LIQUID EQUIVALENT RATES
> OF 0.05-0.15 IN/HR WILL BE POSSIBLE...MAINLY IN HEAVIER
> SLEET/FREEZING RAIN BANDS.
>
> DISCUSSION...AT 21Z...RADAR LOOP SHOWS A LARGE AREA OF RAIN WITH
> EMBEDDED THUNDERSTORMS OVER ERN OK AND NWRN AR SPREADING TO THE
> NORTHEAST. THIS ACTIVITY IS BEING DRIVEN BY ISENTROPIC LIFT OVER A
> FRONTAL BOUNDARY THAT EXTENDS FROM NERN TX THROUGH CNTRL AR...WITH
> SUFFICIENT MID-LEVEL LAPSE RATES FUELING ELEVATED CONVECTION.
> MEANWHILE...THE FREEZING LINE CURRENTLY RUNS FROM A BVO-20 N JLN-IRK
> LINE...WITH THE WET-BULB ZERO LINE RUNNING FROM ROUGHLY
> TUL-JLN-COU-UIN. A COMBINATION OF EVAPORATIVE COOLING AND MODEST
> LOW-LEVEL COLD ADVECTION SHOULD ALLOW THE FREEZING LINE TO MOVE
> SOUTH WITH TIME AS HEAVIER PRECIPITATION OVERSPREADS THE REGION.
>
> STRONG LOW-MID LEVEL FRONTOGENESIS IN THE 21-03Z TIMEFRAME SHOULD
> MAINTAIN ASCENT OVER THE REGION THROUGH THE EVENING...WITH BANDING
> AND POTENTIALLY SOME RESIDUAL UPRIGHT BUOYANCY MAINTAINING
> OCCASIONALLY MODERATE/HEAVY PRECIP RATES. THE NRN PART OF THE MCD
> AREA IS LIKELY TO CHANGEOVER FROM SLEET TO SNOW BY 00Z...WITH NARROW
> TRANSITION ZONES OF SLEET AND FREEZING RAIN FROM NW TO SE SOUTH OF
> THE SNOW AREA AS THE COLD AIRMASS GETS PROGRESSIVELY MORE SHALLOW.
>
> ..DEAN.. 01/12/2013
>
> ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
>
> ATTN...WFO...ILX...LSX...DVN...SGF...EAX...TSA...TOP...ICT...
> OUN...
>
> LAT...LON 35249706 35689747 37249612 38519466 39289356 40079229
> 40499130 40499003 40108960 39399042 38269185 37619269
> 36189464 35249706
>
> Read more
>
>
>
> To change your subscriptions or preferences log in to your Subscriber
> Preferences Page with your e-mail address.
>
> Delete profile
>
> For questions or problems with the subscription service, please contact
> support@xxxxxxxxxxxxxxx.
>
>
> The use of the logo does not imply an endorsement by the NOAA/NWS
>
> GovDelivery provides this service using unaltered NOAA/NWS products. ·
> 1-800-439-1420
Other related posts:
