National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
735
FXUS61 KPBZ 141118 AAA
AFDPBZ

Area Forecast Discussion...UPDATED
National Weather Service Pittsburgh PA
718 AM EDT Mon Oct 14 2019

.SYNOPSIS...
Dry, seasonable weather will continue until a cold front brings
showers and breezy conditions to the region on Wednesday.

&&

.NEAR TERM /THROUGH TUESDAY/...
715am update...minor tweaks to grids accounting for latest sfc obs,
satellite imagery, and hi-res models, but the overall forecast
message remains the same.

Previous Discussion...

A shortwave rotating around the upper level low across the northern
Great Lakes will help drop a cold front southward across the CWA
this morning. Lack of moisture and displacement from upper support
will keep precipitating activity non- existent along the front as it
crosses our area. The only change to the sensible weather will be
increased cloud coverage, a WNW wind shift and a slightly cooler
afternoon today than on Sunday.

As the aforementioned cyclone lifts northeastward, another trough
will drop out of Alberta and into the Upper-Midwest. Ahead of this
system, southerly flow and WAA over our region will result in
Tuesday being the warmest day of the work week. The temperature will
range from the 60s to lower 70s in the afternoon.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
By midnight Wednesday, the aforementioned low is progged to be over
Michigan, with a cold front extending southward through the Ohio
Valley. The frontal rainband will likely expand as it crosses the
CWA, owing to deeper moisture and enhanced ascent under the left exit
quadrant of the southern stream ~150 kt jet streak. Ensemble
guidance suggest somewhere in the vicinity of a half inch of rain
will fall through the first half of Wednesday as the front crosses.
Some select model guidance suggests lapse rates steep enough to
support a few cells capable of lightning, but have chose to leave out
of forecast package at the moment due to guidance spread.

Gusty winds will also accompany the front and persist into Thursday.
Wind speeds will likely be under threshold for an advisory for most
of the region with the exception of the highest elevations (>3000 ft)
in the Allegheny Front, which may very well see wind sustained above
30 mph overnight Wednesday.

Cloud cover w/ scattered lake-enhanced showers will persist across
the area on Wednesday and through much of Thursday as cold cyclonic
NW flow crosses the warm Lake Erie and moves onto the Allegheny
Plateau and ridges. Both days may feel a bit chilly for mid-October
as the cool air and cloud cover keeps the temp to the upper 40s to
low 50s during the afternoon each day.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
The extended period will feature a shift in the pattern from the
cool, mid-week dreariness mentioned above. The synoptic scale wave
pattern will prograde and the CWA will be under the influence of
ridge as it moves overhead. No precip and a mostly sunny sky will
help temps rise to the upper 50s and lower 60s for highs on Friday.

Seasonably warm weather and mostly dry conditions can be expected
over the weekend as the region will sit in southerly flow between
west Atlantic high pressure and deep central-CONUS troughing. Global
models differ on exact timing, but confidence is high that another
low will bring rain to the area sometime the first half of next week.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
Dry air on the flank of the broad and deep srn Canada low wl
maintain VFR through Monday. A reinforcing cold front is progged to
cross the region Monday, resulting in a WSHFT to the W-NW and sct-
locally bkn CU. Light wind wl also persist until FROPA, when gusts of
15 to 20 kt can be expected Monday afternoon as mixing deepens with
warming.

.Outlook...
Restrictions and gusty sfc wind are likely Wed as strong low pres
crosses the Great Lakes.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...None.
OH...None.
PA...None.
WV...None.

&&

$$