Area Forecast Discussion
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FXUS61 KPBZ 220813
Area Forecast Discussion
National Weather Service Pittsburgh PA
413 AM EDT Wed Mar 22 2017
Much colder temperatures today and the morning clouds will
eventually dissipate, providing lots of sun this afternoon.
Temperatures will moderate into the weekend with rain chances
returning on Friday.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Strong cold advection today will result in temperatures 10-15
degrees below normal. Will leave in the mention of snow showers
across the far northeast this morning, as a snow band off of
eastern Lake Erie may clip some of those counties. Winds are not
optimal for additional development although a morning flurry
cannot be ruled out over the rest of the I-80 corridor. Some of
today`s chill will be offset by a full late March sun, as high
pressure brings a very dry atmosphere to the region. Gusty
north-northwest winds will continue throughout the day.
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
High pressure will maintain dry conditions through Thursday with
moderating temperatures expected.
As models begin to get a better handle on the progression of a
warm front Thursday night/Friday morning, and its associated
precipitation, as well as the thermal profile ahead of the
boundary, the risk for widespread wintry mix is beginning to
subside. The tough part of the forecast is where models are
pin pointing the best locations for measurable precipitation,
late Thursday night, is where temperatures could be cold enough
to cause some headaches. The other question will be, since we
are now in late March and temperatures are expected to warm on
Thursday, overnight cooling will be key and this will be
retarded by the rapid onset of mid clouds Thursday evening. Will
keep in a mention of frozen precipitation across the far north
and northeast, but this is done so with low confidence and based
solely on model thermal profiles.
Showers are expected on Friday, although how much coverage
there will be is still in question. Strong warm air advection on
Friday will allow for above normal temperatures.
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A fairly-active, split-stream jet pattern is expected for the
remainder of the forecast, with a series of closed lows expected
in the swrn CONUS and a progressive northern stream.
Moisture spreading ahead of these southern-stream lows will
bring a wetter and cloudier (but warmer) period into early next
week. Precipitation will be driven by the passage of these
ejecting lows, the timing of which is not clear at this time.
.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
High MVFR-low VFR stratocu cloud shield will cover most ports
through mid-morning. After this time, a very dry atmosphere
will win out and rapidly decay the clouds, returning all ports
to VFR conditions. Gusty north-northwest winds will be the
other feature of concern, as gusts of 20 to 30 kts are possible
through the entire period. Winds will weaken after sunset.
The next chance for widespread restrictions should come on
Friday with a front tracking across the lower Great Lakes.