... Low pressure will meander over the western Atlantic through Thursday. High pressure will move in from the Midwest through the weekend. A couple of fronts may approach early next week.
NEAR TERM /THROUGH THURSDAY/... ...Update to remove Coastal Flood Advisory for St Marys County. Previous discussion follows...
Low pressure will continue to move northeast well off the New England coast through tonight while high pressure builds toward the area from the Great Lakes. A weak pressure surge ahead of the high will usher in drier conditions from the northwest overnight, and this will allow for clearing skies. This will also cause the winds to tick up a bit for most locations. Therefore, our latest thinking is that frost will be patchy. Did not issue an advisory due to this reason. The best chance for frost appears that it will be over the central Shenandoah Valley and Virginia Piedmont where winds will be lightest.
Min temps will be in the mid to upper 30s for most locations with near 40 in downtown Washington and Baltimore.
The low will continue to loop back to the northwest on Thursday. Since this will increase the pressure gradient, winds will increase with gusts of 20-30 mph likely. There will be much more sunshine, although some cumulus is possible. Temperatures will be a bit warmer with highs in the mid 50s to lower 60s.
SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/... The overall weather pattern will be slow to change Thursday night and Friday due to the pivoting low pressure gyre off the coast. In addition to winds remaining elevated/gusty (perhaps even at times through the night), some mid/high clouds could try to back into the area by Friday. However, no precipitation is expected. Everything will finally begin to move to the east by Friday night, with surface high pressure pushing east of the Appalachians, helping winds to relax. Temperatures will remain fairly steady state, with lows in the mid 30s to lower 40s and highs in the upper 50s to mid 60s.
LONG TERM /SATURDAY THROUGH WEDNESDAY/... Dry conditions with near average temperatures are expected Saturday, with highs reaching the low 60s, as a surface ridge axis moves overhead. Expect some clouds around throughout the day as a departing upper trough slides off the coast. Clouds will briefly thin out, before building back in form the west Saturday night into Sunday, with another upper-level disturbance. Not expecting any rain with this, but just increased clouds. Lows on Saturday night reach the low 40s. High pressure slides offshore Sunday, bringing slightly warmer temperatures, and continued dry weather, with highs in the upper 60s to near 70.
As an upper-level shortwave swings by to our north, some showers are possible Sunday evening/night, but chances are fairly low. Temperatures dip into the mid 40s or so.
Surface high pressure builds over the southeast early next week, with a general warming trend continuing through Tuesday, with highs in the low to mid 70s each day. However, in the upper levels, a weak trough riding on the periphery of a building upper ridge could bring some showers to the area again. Keeping POPs near 30% for now, as coverage will likely be spotty.