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Area forecast discussion 
National Weather Service Pittsburgh PA
558 PM EDT sun Jul 24 2016

Synopsis...
a muggy night as the Mercury only falls back to around 70. A cold
front in name only passes Monday afternoon bringing the chance of
a downpour. Dry for mid week, however above normal temperatures
are forecast to continue. Another cold front will cross in the
late Thursday - Friday time frame.

&&

Near term /through Monday/...
with 6pm update, dropped heat advisory headline from counties
where line of thunderstorms has come through and significantly
dropped temperatures. While much of the line of thunderstorms has
cleared through west central Pennsylvania, storms are continuing
to remain strong/severe across eastern Ohio, the northern West
Virginia Panhandle, and southwestern Pennsylvania. Wet microbursts
continue to be the primary threat along with downpours considering
the high moisture content of the air. Still expect that the bulk
of rainfall will be done by late evening, as upstream rainfall
across northeastern Ohio is falling apart and has no lightning.
Expect quiet but muggy conditions overnight with lows around 70.

A cold front will cross the region Monday afternoon on the
periphery of the mid level anticyclone. This will end the short
heat wave across the area as clouds and timing of the showers
should hold temps in the 80s. Much the case today, ample energy
to tap for storms, especially when morning cap erodes. Best
chance for any severe storm will be south of duj to pit to zzv
line at this juncture. Wet microbursts are possible given a water
loaded sounding. Precipitable waters north of two inches once again support
brief heavy rain. As for a flash flooding threat, the jury is
still out given storms will be moving and training does not appear
to be an issue. The best timing for storms will be late morning to
midday hours in Ohio and mid to late afternoon for PA/WV/MD.

Temps were constructed using the bias-corrected raw blend given
recent performance.

&&

Short term /Monday night through Wednesday/...
the baroclinic zone will be east of the region Monday night. In
its wake lower dewpoints will return, however daytime highs will
remain above normal with widespread mid and upper 80s forecast.
Any residual fog from the previous day rain will scour out by
late Tuesday morning. Dry weather takes command through the
balance of the short term. Zonal flow aloft and a area of high
pressure traversing through the Great Lakes are the culprits for
the stretch of zero precip days. 800 mb temps slowly increase 1-2c
during this period so for the most part daytime highs will be
mirrors of each other.

&&

Long term /Wednesday night through Sunday/...
highlights:
- continued above normal temperatures
- best shot at rain arrives Thursday night into Friday

Overall no real change to synoptic pattern for much of the week
as a broad 500 mb anticyclone dominates the southern 2/3rds of the
Continental U.S.. our mid level height values will fall a few decameters,
but not enough to usher in temps where they should be for this
time of year. Based on 800 mb temps progs...do not see a stretch of
90f+ weather like this weekend. However, would not be surprised
for eastern Ohio to be right around 90f for daytime highs most of
the week.

Baroclinic zone that crosses Monday night weakens and washes out
over the central Appalachians Tuesday as flow become parallel to
the boundary and it encounters increased subsidence. In its
wake, slightly cooler weather than what we have experienced
takes hold for mid week. By weeks end, another shortwave trough
traverses the region sweeping a cold front through. Timing
differences reside with European model (ecmwf) and gefs, but European model (ecmwf) keeps the
recent Summer trend going of shortwaves passing outside peak
heating hours. GFS opts for a Friday afternoon passage. Either
way, the next shot of widespread precipitation appears to be
Thursday night into Friday. Zonal flow re-establishes for the
weekend with temperatures near the climo average of lower to mid
80s.

&&

Aviation /22z Sunday through Friday/...
thunderstorms remain possible over the next few hours at
duj/lbe/mgw into the evening hours as a line moves across the
forecast area. Latest hi res model guidance has the thunderstorm
complex east of the region by 00z. Behind it, some MVFR cigs or
vsbys may be possible, especially at terminals that received heavy
rainfall. With greater confidence in restrictions north, will
keep mention at kfkl and kduj.

Restrictions will be possible Monday with the approach and
passage of a weak cold front.

Outlook /Monday night through Friday/...
after the passage of the cold front Monday night, no widespread
IFR conditions are expected at this time.

&&

Climate...
hot temperatures across the region today may approach record
levels at some sites. Here are a few selected records and
forecasts...

Site forecast record year
Pittsburgh int'l Airport 94 98 1934
New Philadelphia 97 94 1999
Morgantown 95 93 1987
Zanesville 96 95 1999

&&

Pbz watches/warnings/advisories...
Maryland...none.
Ohio...heat advisory until 8 PM EDT this evening for ohz039-048>050-
057>059-068-069.
PA...heat advisory until 8 PM EDT this evening for paz029-031-073-
075.
WV...heat advisory until 8 PM EDT this evening for wvz002>004-012-
021-509.

&&

$$

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