Archive for March, 2011

Spring Storm…updated with RPM snowfall forecast
March 31, 2011

March is going out like a lion, at least over part of the East Coast.

A massive storm will increase the potential for severe thunderstorms in Florida and heavy snowfall over the Northeast.

The low pressure center will track from the northeast Gulf Coast, northward along to Atlantic coast, past New England and into the Canadian Maritime Provinces.

The storm is expected to intensify off the Mid Atlantic coast, generating the worst weather north of Maryland where heavy coastal rain is expected with heavy snow inland.

Rapid Precision Model snowfall forecast by 4pm Friday…click to enlarge

It should be noted that almost all of the precipitation over the next 48 hours should be rain around the Chesapeake Bay region. There is a small chance that a brief period or two of rain mixed with sleet or snow could fall from Baltimore northward into southern Pennsylvania. If that should happen, little or no accumulation is expected.

John Collins


It Snowed……But…..
March 27, 2011

…….it wasn’t much. The area’s early spring “snow event” barely qualified. Our Friday and Saturday forecasts for an inch or less of snow for Baltimore ultimately leaned toward “less”. Observers at BWI-Marshall Airport reported light snow falling between 4:00am and 7:00am. It appears that if any of it stuck to grassy areas it melted away soon after sunrise, at least around Baltimore.

From Annapolis and Washington southward there was enough snowfall for minor accumulations.

856 AM EDT SUN MAR 27 2011


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

                     SNOWFALL           OF
                     /INCHES/   MEASUREMENT


   WASHINGTON             0.2   730 AM  3/27  TRAINED SPOTTER


   1 NNE ROSEDALE           T   733 AM  3/27  TRAINED SPOTTER

   SAINT CHARLES          0.6   850 AM  3/27  NWS EMPLOYEE
   2 ESE BRYANS ROAD        T   340 AM  3/27


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

                     SNOWFALL           OF
                     /INCHES/   MEASUREMENT


   1 SE DEALE             0.4   800 AM  3/27  COCORAHS

   1 W PRINCE FREDERICK   0.7   800 AM  3/27  COCORAHS


   2 ESE BRYANS ROAD MD   0.5   800 AM  3/27 COCORAHS

   7 ESE BRANDYWINE       0.9   800 AM  3/27  COCORAHS

   1 NE LEONARDTOWN       1.0   700 AM  3/27  COCORAHS
   1 N RIDGE              0.7   800 AM  3/27  COCORAHS

National Weather Service radar showed that the snow was east of Baltimore by 8:20am but still falling south of Washington and Annapolis.

The morning satellite image from NASA shows the bulk of the storm passing to the south of the region.

The rest of the day Sunday should be uneventful with a mix of clouds and sun with chillier than usual temperatures in the 40s.

A weak disturbance will pass to the south of the area Monday and the next best chance for precipitation will be mid week. By that time temperatures will be warmer and rain is likely.

John Collins

Latest Weekend Snow Accumulation Forecast
March 25, 2011

Snowfall Forecast for to enlarge

With just a week to go in the month we’ve had just a trace of snow, officially, down at BWI-Marshall this March.  Normal March snowfall is 2.4″.  However, a storm tracking south of the region may get that March snow total back to near normal this weekend.  The RPM model shows some heavy, wet, Spring snow in the mountains of western Virginia and a couple inches of snow east of the mountains.  The track of the storm and ground temperatures will be critical, so stay tuned for updates.

Tom Tasselmyer

Spring Snow Update
March 25, 2011

It hardly feels like spring today. Plenty of sun so far but temperatures have warmed only into the mid 40s after a morning start in the upper 20s and low 30s.

Two weather disturbances continue to develop to the west and are on tap the move into the cold air this weekend.

The afternoon satellite image shows clouds from one disturbance moving into Arkansas and with another disturbance to the northwest of that. High pressure, rooted in cold, Canadian air, reaches into the Mid Atlantic region.

The storms out west will slip under the southern edge of the cold air and pass mostly to the south of Baltimore over the next couple of days.

The first disturbance comes in this evening, passing mostly south with only limited moisture.

The second disturbance starts to move into the area late Saturday

The Saturday evening forecast map shows the low pressure center as it moves out of Arkansas toward Georgia. The Baltimore area will be on the north edge of the precipitation shield of this disturbance and on the south edge of the cold air. An east-west oriented band of snow will likely fall across the area, mostly early Sunday. Some light accumulation is likely, perhaps as much as a couple of inches worth around Baltimore with a bit more to the south and west.

Check for updates on and our weathercasts on WBAL-TV 11.

John Collins

















































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































Winter Trying To Hang Around
March 24, 2011

Water Vapor image of West coast storm heading to enlarge

Forecast storm to enlarge

Forecast snowfall from RPM to enlarge

A storm on the west coast this evening is forecast to track just south of the mid Atlantic over the weekend.  With unseasonably cold air moving south from Canada, this southern storm may bring some Spring snow into Maryland Saturday night and early Sunday.  In recent weeks the ground has had a chance to thaw so snow accumulation will be harder to come by, but during the overnight and early morning hours when temperatures are close to freezing, the snow may stick to colder surfaces.  Our in-house computer model shows 4-6″ of snow from western Virginia into the West Virginia mountains, and 1-3″ of snow east of the mountains by midday Sunday.  Stay tuned, as this forecast will most likely need to be tweaked.

Tom Tasselmyer


Two Tropical Cyclone Names Retired
March 17, 2011

The World Meteorological Organization has decided to retire two names from the lists used for tropical cyclones in the Atlantic and eastern North Pacific oceans…here is the press release from the U.S. National Oceanic and Atmospheric Administration:

Two Tropical Cyclone Names Retired from List of Atlantic Storms

March 16, 2011

Hurricane Igor as it strikes Newfoundland on September 21.
Hurricane Igor as it strikes Newfoundland on September 21.
High Resolution (Credit: NOAA)

Two tropical cyclone names in the Atlantic were retired from the official name rotation by the World Meteorological Organization’s hurricane committee because of the deaths and damage they caused in 2010. The committee issues the list of potential names for tropical cyclones to be used every six years for both the Atlantic and eastern North Pacific basins.

The names Igor and Tomas in the Atlantic would have appeared again in 2016 but will no longer be used.  In their places will be Ian and Tobias.

Details of the retired 2010 named storms are shown below:

  • Igor was a classic Cape Verde hurricane, reaching Category 4 strength with 155 mph winds on Sept. 14, while located about 600 miles east of the northern Leeward Islands. The storm weakened to a Category 1 hurricane when it struck Bermuda on Sept. 19. Igor grew in size, with the area of tropical-storm-force winds becoming roughly 750 nautical miles wide.  Igor made landfall on Sept. 21 near Cape Race, Newfoundland.  It was the most damaging hurricane on that island in 75 years. Igor killed three people along its path.  Damage in Newfoundland is placed at almost $200 million U.S. dollars.
  • Hurricane Tomas moves between Haiti and Cuba on November 5.
    Hurricane Tomas moves between Haiti and Cuba on November 5.
    High Resolution (Credit: NOAA)

    Tomas became a hurricane on October 30 shortly after striking Barbados. It strengthened to a Category 2 storm striking  St. Vincent and St. Lucia, becoming the latest hurricane on record (1851-present) to strike the Windward Islands. After weakening to a tropical depression over the central Caribbean Sea, Tomas regained Category 1 strength on November 5 and moved between Jamaica and the southwest peninsula of Haiti, through the Windward Passage. It weakened just below hurricane strength before reaching the Turks and Caicos Islands.  Fourteen people are confirmed as dead, or missing, on St. Lucia. Total damage there is estimated to be around $500 million U.S. dollars. Heavy rains associated with Tomas triggered floods and landslides in Haiti. Haiti’s meteorological services states that the death toll in Haiti was 35.

More Wet Weather
March 9, 2011

Another big rainmaker is on the way.

The mid-day Wednesday satellite image shows the storm complex that covers the eastern half of the country.

Low pressure areas headed for the Great Lakes will be responsible for pulling huge amounts of Gulf and Atlantic moisture into the Mid Atlantic region over the next 48 hours. The potential rainfall totals may be higher than those recorded last Sunday.

The ground is saturated from recent rain and snow so the runoff from this developing storm may result in flooding. Flood Watches are in effect across the area. Gusty east to southeast winds will likely pile water up along the western shore of the Bay, resulting in unusually high tides. Creeks, streams and rivers that drain into the Bay may back up as well.

Check in at from time to time for updates and tune in WBAL-TV 11 for the latest from Tom, Tony and me.

Stay dry.

John Collins

A Tale of Two Winters
March 4, 2011

While March and April can still produce winter weather conditions, the higher sun angle and longer days of the weeks ahead generally work against the development of extreme winter-like conditions. With that in mind, the image below summarizes this most recent winter and compares it to the extremes the area experienced the previous year.

The record books for March show that the daily record snowfalls in March are 12 inches or less, with on big exception. On March 28-29, 1942, a storm produced 22 inches of snow, the sixth biggest snow storm on record for Baltimore. 21.9 inches of that snow fell on the 29th.

April daily record snowfalls for Baltimore, with one exception, are less than 5 inches. That exception was a 9.4 inch snowfall on April 1, 1924.

John Collins

Snowy Winter (for most), Winding Down
March 1, 2011

Selected Snowfall Totals and Percent of to enlarge

Temperatures were 20 degrees above normal to finish up the month of February here in Baltimore, but on the cold side of today’s storm, more snow was falling across northern New England.  With “meteorological winter” (Dec., Jan., Feb.) in the record book, and the official start of Spring just 20 days away (March 20th, 7:21 p.m. EDT), it’s interesting to see that Baltimore is one of the only spots in the eastern United States with below normal snowfall this winter.  Snowfall at Central Park in New York City is 326% above normal so far, Pittsburgh 162% above normal, Burlington, VT had their snowiest February ever with 43″ over the past 28 days, and even Atlanta, Georgia has had 3 times its normal snowfall.  But Baltimore, as measured at BWI-Marshall, has had just 14.4″, which is just 92% of normal (although some suburbs have measured over 20″).  Of course, March can still deliver a snowy punch or two, the 30 year average is 2.4″, but with the start of March the countdown to Spring has begun.

Tom Tasselmyer