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Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia
916 PM EDT Tue Jul 26 2016

Synopsis...
a front will remain stationary across the mid-Atlantic region
through the middle of the week. Low pressure will cross the region
Thursday night into Friday. Another cold front will approach
the area early next week.

&&

Near term /until 6 am Wednesday morning/...
convection ongoing this evening out ahead of approaching shortwave
and along weak remnant frontal boundary. Much of the thunderstorm
activity, some severe, has been along south side of instability
gradient where 1500-2000 j/kg remains this evening. Remnant of mesoscale convective system
in WV also progressing eastward this evening, but as it runs into
increasingly stable air mass already worked over earlier this
evening, expecting further weakening. Thus severe threat should be
waning, but potential for heavy rain continues with precipitable
water values 2-2.3 inches. While no significant flooding
currently anticipated, will continue to monitor as some places
have already received locally heavy amounts of rainfall earlier
today. Shower/storm coverage should decrease overnight, but
chances will continue through the night with the presence of a
shortwave/surface reflection. Lows mainly in the 70s.

&&

Short term /6 am Wednesday morning through Thursday night/...
the front may move a little to the south Wednesday, but some
storms will still be possible over southern portions of the area.
The front will begin to lift back north Thursday and Thursday
night as a surface low approaches. Flow will also strengthen aloft
attendant to a short wave trough. There is still some spread in
guidance, but there could be a severe and heavy rain threat
depending on the low track. Temperatures will likely remain above
normal.

&&

Long term /Friday through Tuesday/...
while timing differences remain, overall depiction among long-term
guidance is for an unsettled weather pattern this weekend, as
multiple impulses rotate through broad cyclonic flow aloft. This
will help suppress temperatures back closer to normal, which will be
a welcome relief after the elevated temperatures of earlier this
week. However, even though we have been relatively dry across the
area, multiple rounds of rainfall could create some Hydro issues, as
moisture throughout the column will be plentiful.

Cold front approaches the area Sunday into Monday and is then
forecast to hang up just south of the area Monday and Tuesday.
Current forecast has our area on the "cooler" (m/u80s) and drier
side of the front Monday and Tuesday...with best precipitation
chances generally in the southern portion of the forecast area.

&&

Aviation /01z Wednesday through Sunday/...
mainly VFR through the period, although chances for scattered
showers and some thunderstorms exist through at least the first
half of tonight (mainly cho), and again on Wednesday. Low
pressure crossing the area late Thursday may bring more widespread
storms and rain with more prolonged sub- VFR conditions.

Risk of showers and thunderstorms continues over the weekend, with
warm and moist atmosphere remaining and several impulses moving
through the upper-level flow.

&&

Marine...
primarily sub-Small Craft Advisory conditions expected. The main threat through
Thursday night will come from thunderstorms producing gusty winds.
This threat will greatest over the southern waters. Gradient
winds will likely remain below 15 kt as a weak front is stalled
across the area.

Gradient winds remain sub-Small Craft Advisory Friday through the weekend, though
higher winds and waves can be expected near thunderstorms.

&&

Lwx watches/warnings/advisories...
District of Columbia...none.
Maryland...none.
Virginia...none.
WV...none.
Marine...none.

&&

$$
Synopsis...ads
near term...ads/mm
short term...ads
long term...mse
aviation...ads/mm/mse
marine...ads/mm/mse

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