|Dew Point:||44.0°F (6.7°C)|
|Sea Level Pressure:||29.89" (1012.1 mb)|
Hi 63 °F
Hi 62 °F
Hi 58 °F
Hi 67 °F
Hi 67 °F
Mostly sunny, with a high near 63. Northwest wind around 11 mph, with gusts as high as 20 mph.
Mostly clear, with a low around 42. Northwest wind around 11 mph.
Sunny, with a high near 62. Northwest wind 5 to 8 mph becoming northeast in the afternoon.
Partly cloudy, with a low around 39. Southeast wind around 7 mph.
Mostly cloudy, with a high near 58. South wind 6 to 11 mph.
A slight chance of showers. Mostly cloudy, with a low around 47. Chance of precipitation is 20%.
Mostly sunny, with a high near 67.
Partly cloudy, with a low around 50.
A chance of showers. Partly sunny, with a high near 67. Chance of precipitation is 30%.
Sun Feb 19 2017
SYNOPSIS... A weakening area of low pressure will move into the Atlantic this morning. High pressure will return this afternoon and tonight. A backdoor cold front will enter the area Monday into Tuesday. Another disturbance will cross the area early Wednesday. High pressure will be located off the southeast coast of the United States towards the end of the week.
NEAR TERM /THROUGH TODAY/... Through the 1 and 2 o`clock hours and continuing past 3am, an east-west arc of precipitation can been seen on radar across the forecast area from near Elkins across metro Washington DC. However, clouds are mainly mid deck, and the associated forcing is soley a packet of vorticity around 500 mb. Have not seen visibility restrictions anywhere, making the radar returns sprinkles. Have worded forecast as such. RAP and HRRR runs through the night have been fairly consistent in drying the precip up before sunrise. Grids follow suit.
Heights rise during the daylight hours as an axis of high pressure shifts east today. As a shortwave crosses New England winds become northwesterly. Mixing looks fairly decent, with mean layer gusts in the mid teens (kts). That should offset any cold advection. Guidance temperatures look comparable to yesterday. Will employ a bias-correction to attempt to get cooler readings along the shoreline of the Chesapeake Bay.
SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... From tonight through Monday night, a deep layer ridge axis will translate east, cresting over the East Coast of the United States. However, another lobe of vorticity rotates around the trough axis over the Canadian Maritimes, veering winds north/northeast and sending a backdoor cold front toward the Mid Atlantic. The actual cool-down has been challenging to forecast-- placement, timing, and intensity; latest guidance is focusing more on late Monday afternoon/Monday night (northeast Maryland) into Tuesday (down to the Potomac River). Will follow that lead at this time. Aside from temperatures concerns, the period looks mostly sunny and dry. For that matter, the period will also be mild for late February, just not as warm as current.
Meanwhile, a deep-latitude, sharply amplified shortwave will be crossing the country. It will be arriving in the Appalachians Tuesday night. It`s hard to discern if there will be any surface reflection. That once again makes precipitation prospects questionable. Have confined PoPs Tuesday afternoon to a slight chance northwest of Charlottesville-DC-Baltimore and lowered PoPs Tuesday night to 20-30 percent areawide. Clouds will be increasing though, beginning on Tuesday.
LONG TERM /WEDNESDAY THROUGH SATURDAY/... Wednesday through the first part of the weekend will continue the unseasonably warm weather. On Wednesday high pressure settles off the Southeast coast and remains there through the early Saturday. Generally dry weather will be the rule but models do show an area of low pressure moving across the Great Lakes region early Thursday that could help draw up sufficient moisture for a few showers then. Meanwhile low pressure develops in the southern Plains Wed and deepens as it moves northeast into the Great Lakes region Friday night. A cold front will extend from this low that will cross the region on Saturday. Ahead of the front will see an decent plume of moisture. Depending on the timing of the cold front on Saturday...there could be sufficient instability around to fire off thunderstorms along the front as it crosses the region. High pressure builds in Saturday night.