The Mid Atlantic Region has been a little short of rain in the past few weeks (1.06 inches below average in September at BWI) but generous rain fall this past summer has kept everything green.
Down under, spring has begun and eastern Australia is in the grip of a severe drought. The sky in Sydney has turned red from dust being blown over the region.
The NOAA satellite image below clearly shows the dust over the eastern edge of the continent.
John Collins
Summer is winding down and the numbers show the direction we are headed.
John Collins
Today is the anniversary of Hurricane Floyd’s passing along the Mid Atlantic coast.
The National Weather Service chart above shows the track of the storm. The deep red and orange shaded part of the track indicate that portion of the path at which the storm was hurricane strength, deep red being the strongest. Highest sustained winds reached 156 mph. The yellow portion of the track indicates the portion of the path that the storm was at tropical storm strength.
On September 16 Floyd moved northeast out of coastal North Carolina as a hurricane and was downgraded to a tropical storm as it moved along the DELMARVA coast.
The biggest impact of Floyd over the Mid Atlantic region was the rainfall. The NOAA image below outlines the rain totals from the storm along the Atlantic coast.
The National weather Service map below is a detailed rainfall report for the area west of the Chesapeake Bay.
John Collins
The very wet low pressure system that was off the coast Friday spent Saturday over southeast Pennsylvania. This inland position took the bulk of the rain north of Maryland but because of the low’s proximity to the area, cloud cover was considerable on Saturday with periodic drizzle and temperatures stuck in the 60s. There were sun breaks southwest of Baltimore and those locations saw temperatures rise into the low 70s.
The map below shows surface weather conditions Saturday evening.
The low pressure center is in the process of transitioning back out over the water with a new low developing south of Cape Cod. As the low continues to move farther east, the persistent cloud deck over the area will dissipate. The outlook for Sunday is a little brighter.
The rain on Friday was significant. Below is a sampling of area rain totals:
In the tropics, Fred is losing its’ identity as a tropical system.
In the satellite image above, the remnant low is centered just south of the bright plume of clouds on the far right. The remnant low is expected to move to the west-northwest over the next few days. Given the right set of circumstances there is a remote chance that the storm could reorganize and strengthen at some point in the future. There is quite a bit of thunderstorm activity along the Gulf coast. Tropical development is not expected but the unsettled weather and moisture is likely to move toward the Mid Atlantic region by the middle or end of the coming week.
John Collins
The “Friday Soaker” that John analyzed below produced some impressive rainfall totals from southern Pennsylvania to southern Maryland. The map of selected reports shown here matches well with the radar estimated rainfall. A solid 2-5″ fell in a band from Ocean City northwest to York and Lancaster. Cecil County was hit hard with over 5.5″ at Colora!
Tom Tasselmyer
The storm off the Mid Atlantic coast finally pushed close enough to the coast to generate some significant rain across the area.
The image above is the radar rainfall estimate from the Sterling, VA radar.
The late afternoon satellite image shows the storm spinning slowly toward New England. The image below shows the late afternoon surface conditions.
As the storm pulls away Saturday, a disturbance rotating around its’ southwest quadrant may stir up some spotty shower activity over Maryland but, by and large, the day should be dry. The weekend should be capped off Sunday with some nearly perfect late summer weather.
In the eastern Atlantic, Fred has been downgraded to a tropical storm and is forecast to continue the weakening trend.
Southeast of Fred a new tropical wave is coming off the west African coast and has a small chance for further tropical development.
John Collins
Well, the storm off the Mid Atlantic coast is still stalled.
Most of the significant rain activity is north of the storm center. A high pressure ridge over the northeast U.S. has more or less prevented the storm and its’ rain from moving very much so rainfall over the Baltimore-Washington area has been spotty and the weather has actually been fairly decent.
Rainfall has been pushing westward onto the DELMARVA Peninsula Thursday evening and the trend is expected to continue. Areas east of the Bay, including northeast Maryland could receive up to one inch of rain in the next 24 hours. West of Baltimore, however, rain totals may amount to one half inch or less.
A bulls-eye for up to three inches of rain is forecast for parts of New Jersey.
The beautiful satellite image above show the active weather over the Atlantic Ocean Thursday evening. Two non-tropical storms are churning in the western Atlantic. One is the storm off the Mid Atlantic Coast and the other is a disorganized cluster of storms reaching north from Cuba. In the eastern Atlantic, Hurricane Fred continues to spin 740 miles west of the Cape Verde Islands. Fred’s winds have weakened to 90 mph and the storm is expected to stay out at sea.
John Collins
Wednesday weather remains unsettled over the Mid Atlantic states.
I have annotated a few features on the midday satellite image. An upper level low pressure area (yellow “L”) is centered over the upper Ohio River Valley. It is an extension of a much larger low over northeastern Canada. At the surface, a low (red “L”) is still off the Mid Atlantic coast and a high (red “H”) reaches from Canada into the Great Lakes and New England. The drier air air under the high is evident from the clear conditions over the Great Lakes and upstate New York. Sun breaks have developed in the clouds over Maryland and sunshine dominates over much of the southern half of Virginia. The combination of these systems will be in place in some manner, shape and form for the next couple of days and will be responsible for unsettled conditions over the region.
The chart above is the National Weather Service surface map for midday Wednesday. The influence of the Canadian high is reaching into Pennsylvania and western Maryland and, for the time being, suppressing rain chances around Baltimore.
The presence of the upper low and the prospect of the surface low moving westward to the DELMARVA Peninsula is expected to increase rain chances in the next 24 hours.
Out in the eastern Atlantic, Fred has been upgraded to a hurricane.
Fred is still forecast to turn northward and remain far out in the Atlantic.
John Collins
A coastal storm will be moving very slowly northward along the Mid Atlantic coast for the next couple of days. High pressure anchored in Canada is slowing the low’s progress.
Maryland is wedged between these two pressure systems and the resulting easterly surface wind is pushing Atlantic moisture into the mountains. The cloud deck from this moisture is blocking considerable sunlight and temperatures will be on the cool side of normal while these systems are in place.
In some ways this storm looks like a developing tropical system but upper air conditions and the storm’s proximity to land will likely prevent that from happening. This storm will act more like a nor’easter, but without the intensity.
As of midday Monday most of the significant rain is north of the storm center, which is just to the southwest of Cape Hatteras. On Monday the storm will only inch northward and the heaviest rains will probably fall to the south and east of Baltimore. Bands of light to moderate rain are expected to move across central and northern Maryland during the afternoon and evening hours.
Update: 1:00pm … It appears that the area of high pressure to the north is holding the rainfall well to the south of Baltimore, at least for the time being. Sunshine has actually broken through the cloud deck around the metro area. Rain remains in the forecast but will likely be delayed for a few hours in northern Maryland.
In the far eastern Atlantic a new tropical storm has developed.
Fred is spinning off the west African coast, about 350 miles from the southernmost Cape Verde Islands. The storm is expected to remain over the eastern Atlantic with a northward curving track over the next day or two.
John Collins
It looks like the weather will be uneventful for the Labor Day weekend in the Mid Atlantic region.
The Saturday morning composite satellite image includes surface pressure isobars. A large “Bermuda High” pressure ridge over the Atlantic extends from the coast of France to the western Atlantic. Another high pressure ridge extends from eastern Canada south and southwestward to the eastern and central U.S. Wedged between these two ridges is an area of unsettled weather along the Mid Atlantic and southeast coast of the U.S. For Maryland this weekend, the high pressure wins out and holds any rain at bay. Some cloudiness may sneak into the picture by late Sunday or Monday.
The Canadian high pressure ridge is expected to give way to more unsettled conditions over the eastern U.S. by the end of the coming week.
A couple of tropical waves are moving westward along the southern edge of the Bermuda High. This is a very typical setup in the second half of the hurricane season. These two waves are being monitored for further development.
The remnant of Erika remains over Puerto Rico. This area of unsettled weather is expected to move toward the east coast of the U.S. by the end of the week.
Enjoy the holiday.
John Collins
