053
FXUS61 KPBZ 220929
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
529 AM EDT Sun Jun 22 2025
.SYNOPSIS...
A dangerous heat wave is expected to impact the region through
mid-week. Near record breaking high temperatures could occur
Monday and Tuesday. Thunderstorm chances may return mid to late
week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
KEY MESSAGES:
- Extreme Heat Warning/ Heat Advisory in effect today
- +100F heat index values expected early afternoon
---------------------------------------------------------------
5:30am Update: No major changes to the forecast period. A
mesoscale convection system is currently tracking through New
York early this morning. Outflow from this noted disturbance is
developing a band of mid to upper-level clouds. Otherwise, quiet
weather continues.
Previous Discussion:
A ridge axis is building over the Great Lakes and Ohio River
Valley early this morning. As 925mb winds shift from the
southwest to the west, both temperatures and dew points are
expected to rise rapidly over the next 12 hours. Between 10am to
noon, heat index values are forecast to climb into the
upper-90s/near 100F. The Heat Advisory and Extreme Heat Warning
will begin to be in effect during this time.
Areas most likely to reach or exceed 105F heat index include
the Pittsburgh metro--due to urban heat island effect--and the
surrounding valleys.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
KEY MESSAGES:
- Extreme heat continues into Monday and Tuesday; Heat
Advisory/Extreme Heat Warning continues
- Near-record highs and usually warm low temperatures tonight
into Tuesday night
----------------------------------------------------------------
Confidence remains high that the heat wave will persist into
Monday and Tuesday, as mid-level heights continue to rise in
response to a deepening trough along the West Coast. Heat
Advisories and Extreme Heat Warnings remain in effect during the
day and overnight time period. WIth nighttime temperatures
continuing to hold in the low to mid-70s, minimal relief from
the heat is expected, increasing stress on the body and
potentially straining the power grid by the third consecutive
day of extreme heat.
The probability of reaching or exceeding 95F is elevated --above
75%--across several climate sites for both Monday and Tuesday.
Record highs and record-warm overnight lows are at risk; refer
to the climate section for further details.
Although hot and humid surface conditions will support high
instability aloft, rain chances remain minimal due to the
absence of a lifting mechanism and a strong cap of warm air
limiting cloud formation and growth.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
KEY MESSAGES:
- Ridge weakens Wednesday into Thursday
- Severe weather chances could return late week
- Heat headlines may continue into Thursday
-------------------------------------------------------------------
Ensemble model guidance indicates a weakening of the ridge over
the East Coast by Wednesday into Thursday, coinciding with a
gradual weakening of the West Coast trough. While hot conditions
will persist through Thursday --with highs in the low-90s and
elevated heat index values--additional heat-related headlines
may be necessary.
As the ridge breaks down, the severe weather threat--previously
focused over Canada---shifts back into parts of our region. The
potential for organized convection increase late in the week,
with joint probabilities of favorable shear (30kts) and
instability rising from around 10% Tuesday to over 70% Thursday.
Machine learning guidance continues to highlight the East Coast
as an area of concern between Thursday and Sunday, with several
days showing a 30-45% probability of hazardous weather in the
form of severe storms.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
VFR is expected through the TAF period under a building ridge of
high pressure. The CU rule and model soundings indicate a few
diurnal cumulus clouds will develop today. A few high clouds
will also cross the area as storms track well to our N-NE.
Outlook...
VFR is expected through Tuesday under a strong ridge. Potential
for restrictions and showers/thunderstorms return Wednesday and
Thursday as the ridge begins to drift south.
&&
.CLIMATE...
Daily record high maximum (left) and daily record high minimum (right)
temperatures will be in jeopardy starting this coming Sunday:
Sunday June 22nd
Pittsburgh, PA: 98F (1988) 75F (1988)
Zanesville, OH: 99F (1988) 71F (1997)
Morgantown, WV: 96F (1923,1988) 73F (1988)
Dubois, PA: 92F (2024) 69F (2024)
Wheeling, WV: 95F (1923, 2024) 72F (2011)
New Philadelphia, OH: 97F (1988) 71F (1997)
Monday June 23rd
Pittsburgh, PA: 95F (1894) 76F (1888)
Zanesville, OH: 96F (1899) 70F (1975)
Morgantown, WV: 95F (1899) 71F (1957)
Dubois, PA: 88F (1966) 66F (2017)
Wheeling, WV: 94F (1948) 69F (2013)
New Philadelphia, OH: 97F (1988) 72F (1948)
Tuesday June 24th
Pittsburgh, PA: 96F (1882) 72F (1884)
Zanesville, OH: 98F (1930) 73F (1937)
Morgantown, WV: 94F (1921, 1949) 76F (1924)
Dubois, PA: 88F (1966) 67F (2013)
Wheeling, WV: 98F (1933, 1943) 73F (1908)
New Philadelphia, OH: 94F (1964) 70F (1975)
Wednesday June 25th
Pittsburgh, PA: 98F (1988) 75F (1952)
Zanesville, OH: 101F (1988) 72F (1952)
Morgantown, WV: 94F (1921, 1952, 1988) 74F (1952)
Dubois, PA: 91F (1966) 67F (2000)
Wheeling, WV: 97F (1943) 75F (1952)
New Philadelphia, OH: 92F (1966, 2002, 2005) 68F (2013)
Thursday June 26th
Pittsburgh, PA: 95F (1966) 75F (1952)
Zanesville, OH: 97F (1952) 73F (1952)
Morgantown, WV: 96F (1952) 74F (1952)
Dubois, PA: 91F (1966) 66F (2000)
Wheeling, WV: 96F (1943, 1952) 73F (1952)
New Philadelphia, OH: 99F (1988) 71F (2022)
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
PA...Heat Advisory from 11 AM this morning to 8 PM EDT Wednesday
for PAZ007>009-013-015-016-022-031-074-076>078.
Extreme Heat Warning from 11 AM this morning to 8 PM EDT
Wednesday for PAZ014-020-021-029-073-075.
OH...Heat Advisory from 11 AM this morning to 8 PM EDT Wednesday
for OHZ039>041-048>050-057>059-068-069.
WV...Heat Advisory from 11 AM this morning to 8 PM EDT Wednesday
for WVZ001>004-012-021-509>513.
&&
$$
SYNOPSIS...Hefferan
NEAR TERM...Hefferan
SHORT TERM...Hefferan
LONG TERM...Hefferan
AVIATION...WM
CLIMATE...