Archive for February, 2011

Rough Monday
February 28, 2011

Today’s warm up will be welcomed but it comes with a price. The rush of warm air ahead of a strong cold front brings the potential for severe weather.

Courtesy: NOAA (Updated 1:20pm EST)

The map above outlines the various Warnings, Watches and Advisories in effect as of 10:00am 1:20pm Monday. The yellow shaded counties are under a Tornado Watch until 4:00pm. The western portion of the Baltimore area southern half of Maryland west of the Bay is included in this Watch.

The overall picture has the Mid Atlantic region in the “Slight Risk” category for severe weather on Monday.

The morning satellite image shows the extent of the storm. Note that the heaviest cloud deck has moved just north of Baltimore, allowing for sunshine and warming temperatures.

Courtesy: NOAA    (8:38am EST     28 Feb 2011)

The morning surface map shows the sweep of warm, moist Gulf air ahead of the storm system into the Ohio River Valley and the Mid Atlantic states. Note that the warm front was straddled across Maryland. The forecast calls for the front to continue its’ northward progress, allowing for unseasonably warm temperatures across the region but also contributing to an unstable environment that is ideal for storm development.

Check in with wbaltv.com frequently for updates on today’s weather and use our Interactive Radar to track storms nearby. Be sure to tune in Sandra and Tom on  WBAL-TV 11 for bulletins at any time and for scheduled news and weather at Noon, 5:00pm and 6:00pm.

John Collins

Gulf Stream View
February 24, 2011

The Wednesday night satellite image provided a fairly good view of the Gulf Stream current moving up the southeast U.S. coastline, turning northeastward at Cape Hatteras.

John Collins

Snow Totals
February 23, 2011

The Wednesday afternoon satellite image from NASA clearly displays the area around Baltimore that received snow from the latest storm.

 

Below is a listing from the National Weather Service on snow reports from this latest storm.

PUBLIC INFORMATION STATEMENT
SPOTTER REPORTS
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1257 PM EST TUE FEB 22 2011

THE FOLLOWING ARE UNOFFICIAL OBSERVATIONS TAKEN DURING THE PAST
31 HOURS FOR THE STORM THAT HAS BEEN AFFECTING OUR REGION.
APPRECIATION IS EXTENDED TO HIGHWAY DEPARTMENTS...COOPERATIVE
OBSERVERS...SKYWARN SPOTTERS AND MEDIA FOR THESE REPORTS.  THIS
SUMMARY IS ALSO AVAILABLE ON OUR HOME PAGE AT WEATHER.GOV/BALTIMORE

********************STORM TOTAL SNOWFALL********************

LOCATION          STORM TOTAL     TIME/DATE   COMMENTS
                     SNOWFALL           OF
                     /INCHES/   MEASUREMENT

DISTRICT OF COLUMBIA

...DISTRICT OF COLUMBIA...
   AMERICAN UNIVERSITY    0.5   615 AM  2/22  TRAINED SPOTTER

MARYLAND

...ALLEGANY COUNTY...
   1 N FROSTBURG          4.1   700 AM  2/22  CO-OP OBSERVER
   2 NNW FROSTBURG        4.0   700 AM  2/22  TRAINED SPOTTER
   FROSTBURG              4.0   900 AM  2/22  TRAINED SPOTTER
   1 SSE CUMBERLAND       4.0   700 AM  2/22  CO-OP OBSERVER
   ECKHART MINES          4.0   400 AM  2/22  TRAINED SPOTTER
   1 ENE MOUNT SAVAGE     0.5   714 PM  2/21  TRAINED SPOTTER

...ANNE ARUNDEL COUNTY...
   BWI AIRPORT            3.2   700 AM  2/22  AIRPORT
   1 NE GREEN HAVEN       3.0   600 AM  2/22  CO-OP OBSERVER
   ANNAPOLIS              3.0   600 AM  2/22  WMAR REPORT.
   GREEN HAVEN            3.0   600 AM  2/22  WMAR REPORT.
   3 SW LOTHIAN           3.0   500 AM  2/22  TRAINED SPOTTER
   MAYO                   2.0   600 AM  2/22  WMAR REPORT.
   GAMBRILLS              2.0   600 AM  2/22  WMAR REPORT.
   ARNOLD                 2.0   600 AM  2/22  WMAR REPORT.
   SEVERN                 1.8   615 AM  2/22  TRAINED SPOTTER
   EASTPORT               1.3   730 AM  2/22  TRAINED SPOTTER
   1 NNW PAROLE           1.0  1130 AM  2/22  TRAINED SPOTTER
   1 WNW GREEN HAVEN      0.5  1145 PM  2/21

...BALTIMORE COUNTY...
   PARKTON                6.3   700 AM  2/22  TRAINED SPOTTER
   1 ESE GLYNDON          5.8   700 AM  2/22  PUBLIC
   1 W HAMPTON            5.7   730 AM  2/22  TRAINED SPOTTER
   1 SE GARRISON          5.1   730 AM  2/22  TRAINED SPOTTER
   1 NE ROSSVILLE         5.1   800 AM  2/22  TRAINED SPOTTER
   RANDALLSTOWN           5.0   600 AM  2/22  WMAR REPORT.
   2 E PERRY HALL         5.0   750 AM  2/22  TRAINED SPOTTER
   2 NW LONG GREEN        5.0   800 AM  2/22  TRAINED SPOTTER
   REISTERSTOWN           5.0   700 AM  2/22  WUSA REPORT
   TOWSON                 5.0   607 AM  2/22  BROADCAST MEDIA
   ESSEX                  4.5   700 AM  2/22  WUSA REPORT.
   PARKVILLE              4.0   800 AM  2/22  TRAINED SPOTTER
   1 NNE ROSEDALE         4.0   800 AM  2/22  TRAINED SPOTTER
   TIMONIUM               4.0   600 AM  2/22  WMAR REPORT.
   1 E OELLA              4.0   700 AM  2/22  TRAINED SPOTTER
   HUNT VALLEY            3.6   130 AM  2/22  28 DEGREES
   PERRY HALL             3.0  1135 PM  2/21  PUBLIC
   1 NE KINGSVILLE        2.8  1200 AM  2/22  MODERATE SNOW
   2 SE ROSEDALE          1.0  1023 PM  2/21  PUBLIC
   1 ENE BENTLEY SPRING     T   705 PM  2/21  TRAINED SPOTTER

...BALTIMORE CITY...
   PIMLICO                4.5   800 AM  2/22  TRAINED SPOTTER
   HAMILTON               4.3   900 AM  2/22  PUBLIC
   2 ESE ARLINGTON        2.0  1145 AM  2/21  26 DEGREES

...CALVERT COUNTY...
   HUNTINGTOWN            0.8   700 AM  2/22  WUSA REPORT.
   PRINCE FREDERICK       0.5   700 AM  2/22  WUSA REPORT.

...CARROLL COUNTY...
   1 SSW MANCHESTER       7.0   700 AM  2/22  TRAINED SPOTTER
   HAMPSTEAD              6.0   600 AM  2/22  WMAR REPORT.
   3 WSW LINEBORO         6.0   215 AM  2/22  TRAINED SPOTTER
   MILLERS                6.0   800 AM  2/22  PUBLIC
   ELDERSBURG             5.0   600 AM  2/22  WMAR REPORT.
   2 E LINEBORO           4.8   100 AM  2/22  CO-OP OBSERVER

...CHARLES COUNTY...
   SAINT CHARLES          0.5   630 AM  2/22  NWS EMPLOYEE

...FREDERICK COUNTY...
   THURMONT               5.0   700 AM  2/22  WUSA REPORT.
   2 NNW NEW MARKET       5.0   540 AM  2/22  TWITTER REPORT
   WALKERSVILLE           5.0   800 AM  2/22  TRAINED SPOTTER
   3 SE EMMITSBURG        4.5   715 AM  2/22  CO-OP OBSERVER
   1 ESE FREDERICK        4.5   600 AM  2/22  TRAINED SPOTTER
   1 E WALKERSVILLE       4.0   220 AM  2/22  TRAINED SPOTTER
   2 ENE MYERSVILLE       4.0   700 AM  2/22  TRAINED SPOTTER
   POINT OF ROCKS         3.0   730 AM  2/22  NWS EMPLOYEE
   FREDERICK                T   734 PM  2/21  EMERGENCY MNGR

...HARFORD COUNTY...
   BEL AIR                7.0   600 AM  2/22  WMAR REPORT.
   NORRISVILLE            6.8   630 AM  2/22  TRAINED SPOTTER
   EDGEWOOD               6.0   730 AM  2/22  PUBLIC
   2 E SCARBORO           6.0   800 AM  2/22  TRAINED SPOTTER
   1 NNE BEL AIR          5.0   800 AM  2/22  TRAINED SPOTTER
   ABERDEEN               5.0   600 AM  2/22  WMAR REPORT.
   FALLSTON               4.3   800 AM  2/22  TWITTER REPORT
   FOREST HILL            4.0   600 AM  2/22  WMAR REPORT.
   2 E NORRISVILLE        0.2   830 PM  2/21  TRAINED SPOTTER

...HOWARD COUNTY...
   2 N COLUMBIA           3.5   545 AM  2/22  TRAINED SPOTTER
   ELKRIDGE               3.0   210 AM  2/22  TRAINED SPOTTER
   1 SSE SIMPSONVILLE     2.9   600 AM  2/22  TRAINED SPOTTER
   FULTON                 2.5   700 AM  2/22  WUSA REPORT.
   1 WSW SAVAGE           2.0   630 AM  2/22  TRAINED SPOTTER

...MONTGOMERY COUNTY...
   2 WSW DAMASCUS         3.4   700 AM  2/22  CO-OP OBSERVER
   LAYTONSVILLE           2.0   130 AM  2/22  PUBLIC
   CLARKSBURG             2.0   700 AM  2/22  WUSA REPORT
   POOLESVILLE            2.0   430 AM  2/22  TRAINED SPOTTER
   1 S MONTGOMERY VILLA   1.8   533 AM  2/22  NWS EMPLOYEE
   1 SE NORBECK           1.5   700 AM  2/22  PUBLIC
   1 NW DAMASCUS          0.5  1140 PM  2/21  MODERATE SNOWFALL
   1 W ROCKVILLE          0.3  1059 PM  2/21  TRAINED SPOTTER

...PRINCE GEORGES COUNTY...
   1 SSE FOREST HEIGHTS   0.5   700 AM  2/22  CO-OP OBSERVER
   1 NW COLLEGE PARK      0.2  1125 PM  2/21  TRAINED SPOTTER
   1 SW COLLEGE PARK        T   905 PM  2/21  TRAINED SPOTTER
   CAMP SPRINGS             T   534 AM  2/22  NWS OFFICE

...WASHINGTON COUNTY...
   HANCOCK                5.8   530 AM  2/22  PUBLIC
   SMITHSBURG             5.0   700 AM  2/22  WUSA REPORT.
   2 SE ANTIETAM          3.7   700 AM  2/22  CO-OP OBSERVER
   2 SW WARRENTON         1.0   847 PM  2/21  TRAINED SPOTTER
PUBLIC INFORMATION STATEMENT
SPOTTER REPORTS
NATIONAL WEATHER SERVICE STATE COLLEGE PA
1028 AM EST TUE FEB 22 2011

**********************24 HOUR SNOWFALL**********************

LOCATION              24 HOUR     TIME/DATE   COMMENTS
                     SNOWFALL           OF
                     /INCHES/   MEASUREMENT

PENNSYLVANIA

...ADAMS COUNTY...
   CASHTOWN 1S            6.6   800 AM  2/22  COOP
   1 SE YORK SPRINGS      6.5   700 AM  2/22  COCORAHS
   YORK SPRINGS           6.5   930 AM  2/22
   HANOVER                6.4   800 AM  2/22  COOP
   2 N ABBOTTSTOWN        5.7   700 AM  2/22  COCORAHS
   BIGLERVILLE            5.2   800 AM  2/22  COOP
...LANCASTER COUNTY...
   HOLTWOOD               5.0   830 AM  2/22
   3 SSE ADAMSTOWN        4.2   700 AM  2/22  COCORAHS

...YORK COUNTY...
NEW FREEDOM 7.0 705 AM 2/22 GLEN ROCK 6.5 706 AM 2/22 DALLASTOWN 6.0 705 AM 2/22 YORK HAVEN 5.2 800 AM 2/22 VALLEY GREEN 5.0 706 AM 2/22 1 ENE VALLEY GREEN 5.0 700 AM 2/22 COCORAHS PUBLIC INFORMATION STATEMENT SPOTTER REPORTS NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 306 PM EST TUE FEB 22 2011 THE FOLLOWING ARE UNOFFICIAL OBSERVATIONS TAKEN DURING THE PAST 10 HOURS FOR THE STORM THAT HAS BEEN AFFECTING OUR REGION. APPRECIATION IS EXTENDED TO HIGHWAY DEPARTMENTS...COOPERATIVE OBSERVERS...SKYWARN SPOTTERS AND MEDIA FOR THESE REPORTS. THIS SUMMARY IS ALSO AVAILABLE ON OUR HOME PAGE AT WEATHER.GOV/PHI ********************STORM TOTAL SNOWFALL******************** LOCATION STORM TOTAL TIME/DATE COMMENTS SNOWFALL OF /INCHES/ MEASUREMENT DELAWARE ...KENT COUNTY... DOVER 4.3 545 AM 2/22 VIOLA 3.1 545 AM 2/22 HARRINGTON 2.0 545 AM 2/22 ...NEW CASTLE COUNTY... NEWARK 5.6 642 AM 2/22 WILMINGTON AIRPORT 4.7 700 AM 2/22 BEAR 4.7 700 AM 2/22 BLACKBIRD 4.4 545 AM 2/22 GREENVILLE 4.3 545 AM 2/22 GLASGOW 4.2 545 AM 2/22 TALLEYVILLE 4.2 545 AM 2/22 HOCKESSIN 4.1 545 AM 2/22 CLAYMONT 4.0 545 AM 2/22 NEW CASTLE 4.0 545 AM 2/22 PRICES CORNER 4.0 545 AM 2/22 WILMINGTON 3.5 849 AM 2/22 MILFORD CROSSROADS 3.2 545 AM 2/22 WHITE CLAY MIDDLE RUN ...SUSSEX COUNTY... ELLENDALE 1.6 545 AM 2/22 LEWES 1.5 630 AM 2/22 STOCKLEY 0.7 545 AM 2/22 BRIDGEVILLE 0.7 545 AM 2/22 LAUREL 0.4 545 AM 2/22 SELBYVILLE 0.3 545 AM 2/22 MARYLAND ...CECIL COUNTY... COLORA 6.0 626 AM 2/22 ELKTON 4.4 645 AM 2/22 ...KENT COUNTY... MILLINGTON 5.5 626 AM 2/22 GALENA 4.0 739 AM 2/22 ...QUEEN ANNE`S COUNTY... STEVENSVILLE 1.5 1110 AM 2/22 ...TALBOT COUNTY... EASTON 1.5 627 AM 2/22
John Collins

Winter Storm Update
February 22, 2011

Water Vapor shows upper low and jet stream...click to enlarge

Surface low tracking east on frontal boundary...click to enlarge

RPM snow forecast...click to enlarge

The first significant snowfall in almost a month continues to move into central Maryland this evening.  Compared to last year’s record-breaking February snowfall, the second month of 2011 has been downright balmy.  Only a trace of snow has been measured so far this month at BWI-Marshall (last February 50″ of snow was measured there), and the average temperature of 37.7F is 3.2 degrees warmer than normal, and a whopping 6.8 degrees warmer than February 2010.

However, a more familiar February weather pattern is unfolding tonight.  Water vapor satellite imagery shows an upper level low pressure system over the upper midwest and a strong jet stream zipping from Baja California into the Ohio valley and mid Atlantic states.  The jet separates bitterly cold, arctic air over New England, from warm, Spring-like air over the southeastern U.S.  Low pressure near the surface has formed on that boundary and  is moving east toward Virginia tonight.  As the low passes south of the region, the cold air over New England should be drawn south into the storm, changing a rain/sleet mix to a period of moderate to heavy snow.  The upper jet stream is carrying the system east/northeast very quickly and the snow should taper off by dawn.

Current indications are that 4-8″ of snow will fall over much of Maryland north of a D.C. to Annapolis to Centreville line.  Some areas near and just north of the Pennsylvania line could receive a little more than 8″.

Tom Tasselmyer

Back To Winter
February 21, 2011

A new storm system is developing and it will provide a wintry mix for the area over the next 24 hours.

The morning satellite image shows the storm stretching from the Midwest to the Northeast states.

The morning surface weather map details what is going on under those clouds. A front is draped across Maryland and on to the west. At 10:00am, temperatures in southern Maryland are about 10-20 degrees warmer than in the Baltimore area. Although the map shows the front to be a warm frontal boundary, the reality is that the front won’t be moving all that much during the day and will push south later in the day and overnight.

The low pressure center over Garrett County will move east today and a second low in the Midwest will take a more southerly track into Virginia tonight, allowing colder air and more snow to move farther south than anticipated over the weekend. This means a little more snow accumulation than originally thought for the Baltimore metro area by the Tuesday morning rush hour.

A computer model used in the WBAL weather office forecasts an accumulation of 2-6 inches of snow from the Annapolis/Washington area northward into southern Pennsylvania with the heaviest accumulations just north of Baltimore, indicated by the darker blue/purple shading.

 

A Winter Storm Watch Warning has been issued for the northern tier of counties in Maryland northward into Pennsylvania and a Winter Weather Advisory is in effect from Southern Baltimore County and Baltimore City southwestward to Washington, DC. A Winter Storm Watch is in effect for southern Pennsylvania.

All of this is subject to some fine tuning so check back with wbaltv.com from time-to-time and watch Tom, Tony and Sandra for the latest on WBAL-TV 11

John Collins

Windy Saturday
February 20, 2011

John Collins

Watch Out For A Windy Saturday!
February 18, 2011

Surface map Friday morning...click to enlarge

Surface map forecast Saturday morning...click to enlarge

Jet Stream forecast Saturday...click to enlarge

RPM near surface wind forecast 6am Saturday...click to enlarge

A strong cold front will whip through Maryland tonight bringing and end to our Spring preview and ushering in strong, potentially damaging winds.  An intense low pressure system passing north of the region will combine with high pressure building in from the Midwest, a strong jet stream aloft, and a surge of cold, dense air, to produce a blustery Saturday.  Computer models are showing sustained winds of 35-45 mph across much of central and eastern Maryland beginning in the pre-dawn hours of Saturday and lasting into the afternoon.  The high winds should begin to diminish after sunset Saturday.  The National Weather Service has issued a High Wind Watch because of the potential for 40 mph sustained winds with gusts to 60 mph.  Stay tuned for updates.

Tom Tasselmyer

 

Temperature Ups And Downs
February 17, 2011

The area in in the midst of a brief and pleasant thaw. Temperatures this week have been on a roller coaster.

High temperatures at BWI-Marshall Airport have been well above the seasonal average this week but are expected to fall below average by the end of the Presidents Day Holiday weekend.

John Collins

Last Year’s Third Big Snow
February 10, 2011

Upper Level Map 7:00am February 8, 2010...click to enlarge

Upper Level Map 7:00am February 9, 2010...click to enlarge

Upper Level Map 7:00am February 10, 2010...click to enlarge

Surface Map 7:00am February 8, 2010...click to enlarge

Surface Map 7:00am February 10, 2010...click to enlarge

The third major storm of the 2009-2010 winter season rolled through the region on February 9th and 10th.  We’ve posted the weather maps that show the meteorological set up that brought the storm.  A low pressure system in the upper levels of the atmosphere over the Dakotas on the 8th combined with a weak trough of low pressure over New Mexico and consolidated into one powerful upper low over Iowa on the 9th.  This upper level system then tracked into West Virginia on the 10th.  The upper level systems initially produced two surface lows, one over Minnesota, and the other over west Texas on the 8th.  These two lows combined into one powerful storm off the Delaware coast by the morning of the 10th.

In the wake of the storm, snowfall records for the area were completely rewritten.  When combined with the blizzard that swept through just four days earlier, three to four feet of snow covered most of central Maryland on the morning of February 11, 2010.  By the end of the month these new Baltimore snowfall records were established:

2nd Snowiest December:  20.1″, December 2009 (20.4″ in Dec. 1966)

Snowiest single month:  50.0″, February 2010 (old record: 40.5″ in Feb. 2003)

Snowiest winter season:  77.0″  2009-2010 (old record: 62.5″ in 1995-’96)

 

John Collins & Tom Tasselmyer

Southern Storm Update
February 10, 2011

Wednesday Evening Surface Map...click to enlarge

The storm responsible for 1 to 2 feet of snow from the panhandle of Texas through Oklahoma to southwest Missouri and northern Arkansas, is still putting down moderate to heavy snow in parts of northern northern Mississippi, Alabama, Tennessee, and Kentucky.  The low pressure system has weakened over the past 24 hours and snowfall totals are expected to diminish as the storm heads for the North Carolina outer banks tonight, then moves off the coast Thursday.  In fact 24 hours ago, the storm was on the New Mexico/Texas border with a central pressure around 1000 millibars, tonight the storm in on the gulf coast east of New Orleans with a central pressure near 1012 millibars.

GFS Forecast for 1:00am Thursday...click to enlarge

GFS Forecast for 7:00am Thursday...click to enlarge

RPM Snowfall Forecast

A split in the jet stream continues this evening with the southern branch expected to dominate; carrying the storm east off the coast and not up the eastern seaboard.  Still, as the system passes south of the region overnight, a period of light snow or snow showers may dust the ground in parts of Maryland, especially south of Annapolis.  Our in-house RPM model is showing an inch or less in these favored areas.  Cold arctic air will pour into the region behind the storm, keeping temperatures below normal for a couple more days.  A Wind Chill Advisory is in effect for western Allegany and Garrett Counties.  After the arctic air slides east, a  modest warm up is expected over the weekend and into the middle of next week.

Tom Tasselmyer