Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Gray ME
238 PM EDT Tuesday Jul 22 2014
high pressure centered to our south will transport increasingly
hot and humid air into the area through Wednesday. A cold front
will approach late Wednesday and bring showers and strong to
possibly severe thunderstorms. The front moves across the region
Wednesday night and exits offshore Thursday morning. High pressure
builds in from the west Friday and Saturday. Wet weather will once
again be possible late in the weekend and early next week as the
next upper trough dives in.
Near term /through tonight/...
at 18z...a 1023 millibar high was centered to the south of New
England. The southerly flow around the high continued to transport
increasingly warm an humid air into the forecast area with
temperatures mainly in the 80s and dewpoints in the 60s. Isolated
sprinkles popped up over southern and western New Hampshire around
noon but have since dissipated. For tonight...we'll be mostly
clear and muggy with lows in the 60s and areas of fog once again.
Short term /Wednesday through Wednesday night/...
any fog should burn off rapidly Wednesday morning with temperatures
quickly warming into the 80s. The coastal plain...with the
exception of middle coast Maine with onshore flow...should touch 90
degrees. With convective available potential energy of 2000 - 3000 j/kg on Wednesday and
approaching front...expect convection to breakout across the
mountains by 18z then race southeast along and ahead of surface
front and a prefrontal trough. Primary threat should be damaging
winds with some marginally severe hail possible in the largest
storms. Precipitable waters approaching 2 inches could aid in localized flash
flooding if cells train.
The activity should wind down quickly Thursday evening as the
front clears the coast with any lingering showers ending
overnight with exception of the immediate coast.
Long term /Thursday through Monday/...
cold front will be sagging southward just south of the County Warning Area early
Thursday morning. Some light anafrontal rainfall may occur
Thursday morning across southern zones...but as the front
continues to push southward drier air will move into the region.
Thereafter...mainly fair weather is expected Thursday night
through Saturday with high pressure building across the area. Late
in the weekend and early next week it looks as though another
strong upper trough will dive southward into the Great Lakes region
allowing US to get into a more moist and meridional flow. This may
mean periods of heavy showers and thunderstorms centered around
Aviation /18z Tuesday through Sunday/...
short term /through Wednesday night/...expecting another round of valley
fog for a couple hours around sunrise Wednesday morning. Wednesday will see a
return to VFR in the morning...but severe thunderstorms and rain are possible at
inland terminals by middle-late afternoon...reaching the coast
Long term...mainly VFR conditions are expected Thursday through
Saturday with patchy late night valley fog possible. Low chance
for ceiling/visibility restrictions on Sunday in scattered showers and thunderstorms.
short term /through Wednesday night/...southerly flow will
increase overnight ahead of the front with building seas and occasional
gusts outside the bays reaching marginal small craft overnight
into Thursday night. Occasional visibility restrictions in fog/haze likely
with a round of strong to severe thunderstorms likely on the
waters Wednesday evening.
Long term...mainly tranquil conditions expected on the waters Thursday
through Sat. It looks like winds increase and seas build Sat night
through Monday in advance of the next cold front.
Marine...Small Craft Advisory from 2 am Wednesday to 6 am EDT Thursday