PBZ issues Area Forecast Discussion (AFD) at Jun 19, 12:32 PM EDT714
FXUS61 KPBZ 191632
AFDPBZ
Area Forecast Discussion
National Weather Service Pittsburgh PA
1232 PM EDT Thu Jun 19 2025
.SYNOPSIS...
Thunderstorm chances increase this afternoon and evening with
the passage of a cold front. Dry weather returns Friday
with excessive heat likely through the middle of next week
under high pressure.
&&
.NEAR TERM /THROUGH TONIGHT/...
KEY MESSAGES:
- Showers and thunderstorms along a cold front with a low end
severe weather and heavy rainfall potential.
---------------------------------------------------------------
Showers and thunderstorms are again expected to develop this
afternoon as a cold front slides through. Plenty of lift will
accompany its passage with mid-level height falls and the right
entrance region of an upper jet. Confidence in development is high,
but the biggest question will be how much instability we're able to
generate before its passage despite the passage itself being at a
favorable time. Morning satellite shows some brief pockets of
clearing which, with how high the sun angle is this close to the
solstice could be enough to warm temperatures a couple degrees
quickly, but the general theme is appearing to be too much cloud
cover for significant destabilization. That said, with modest
southwest flow, warm advection should still allow for temperatures
to reach the upper 70s with dew points in the mid to upper 60s,
warmest to the south. Thus, probability for >750 J/kg SBCAPE and >30
knots of deep layer shear is highest (70-90%) south of Pittsburgh
and only 40-50% to the north.
Some development is already ongoing early this afternoon along a pre-
frontal trough which could muddy the picture further as these could
rob the available instability before the cold front arrival. Given
the environment though, think that the highest severe probability
still likely lies from Pittsburgh and south coincident with the best
overlap of instability and shear. A moist column with PWAT values
still >1.5" could support some heavy rainfall as well. Given
the quicker storm motion, don't think we'll be looking at a
widespread flooding threat, but with how wet the soils are, it
won't take much. This also doesn't support much of a downburst
wind threat, but a damaging straight line wind threat in any
congealed line segments will exist with relatively straight
hodographs. Most likely timing will be after 2pm in eastern Ohio
and 4pm in western PA.
Behind the front, dry air will (finally) work in and aside from a
lingering shower overnight, we'll shut off precipitation chances.
Dew points will dip down to the mid 50s overnight in northwest flow
and provide a brief reprieve from the humidity, but that won't last
long.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
KEY MESSAGES:
- Dry weather returns Friday with temperatures beginning to
warm.
----------------------------------------------------------------
Dry weather continues Friday in the wake of the boundary and we'll
continue that theme well into next week. Building high pressure to
our south will flip flow back to the southwest and bring dew points
back up again. All in all, Friday will be the most comfortable day
of the next seven with highs in the low 80s and dew points in the
mid 60s.
The heat starts to build on Saturday as warm advection ramps up
pulling 850 mb temperatures to 17-19C with some scattered clouds.
This will translate to highs in the upper 80s with some urban area
and valley readings possibly touching 90. Overnight lows will remain
mild in the upper 60s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
KEY MESSAGES:
- Turning drier with excessive heat threat ramping up into next week.
- Potential record high and low temperatures.
- Heat headlines increasingly likely.
-------------------------------------------------------------------
The story of the long term period beginning Sunday is a prolonged
period of dangerous, excessive heat.
Ensembles exhibit quite a bit of certainty on a strong upper ridge
building across the eastern CONUS with a 90+% chance of 500 mb
heights >590 dam. Ensemble mean 850 mb temperatures soar to 21-23C.
NBM probability for highs >90F is remarkably high at 80+% Sunday
through Thursday. Notably, probability for highs >95F is
60-80%, highest in the urban areas, on Monday and Tuesday. Dew
points are progged to be in the mid 70s, but we'd ordinarily
have a tough time topping highs out in the mid 90s with dew
points remaining in the 70s, so it's possible that we find a
middle ground with low 90s temps and upper 60s/low 70s dew
points. Either way, heat indices are very likely to top the
100-105F range for several consecutive days. Compounding the
effects of excessive daytime heat will be little relief at
night; probability for lows >70F is 80-90+% Sunday- Wednesday
nights.
One thing to keep in mind is that at times we can get affected by
diurnally driven clouds and precipitation in these patterns with
such warm temperatures and plenty of near-surface moisture. So while
that could have localized, brief cooling effects, the takeaway
message at this point is that several days of excessive, dangerous
heat is increasing likelihood across the entire area and compounding
effects could be significant. Heat headlines are very likely within
the next 24 to 36 hours. Record lows and highs may be in jeopardy as
well... see the climate section below for more. In preparation
a few days out, it is a good idea to find out more about your
local cooling shelters and consider altering outdoor plans to at
least outside of the afternoon peak heating window.
By mid to late week, low confidence convective development could
advance over the Great Lakes region and track into our area bringing
a return of showers and thunderstorms. Some of these could be
stronger, and NCAR's medium-range machine guidance highlights the
Ohio River Valley as an area for hazardous weather (15-30% chance)
during this timeframe.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
MVFR stratocu have overspread the area this morning, with slow
improvement to VFR possible mainly south of I-80 by this
afternoon. Scattered showers and thunderstorms are once again
forecast across the area during late morning and afternoon hours
as a front makes its way through the region from the northwest.
Southwesterly winds increase with the onset of deeper mixing,
with gusts to 20-25 knots possible at most terminals. The front
is expected to cross through the region after 18z and will serve
as a focus for a broken line of showers and thunderstorms.
Damaging wind gusts and locally heavy rainfall remain the
largest threats for these storms.
Outlook... Outside of lingering moisture fueling isolated to
scattered showers Friday, the outlook favors a prolonged period
of VFR Friday afternoon through at least early next week under
the influence of high pressure and large ridging overhead. A
heat wave is looking more and more likely to settle in Sunday
through at least Tuesday, with latest ensembles suggesting high
probabilities for temperatures above 90 degrees each afternoon
during that time.
&&
.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...None.
OH...None.
WV...None.
&&
$$
SYNOPSIS...Hefferan/MLB
NEAR TERM...MLB
SHORT TERM...MLB
LONG TERM...MLB
AVIATION...Cermak
CLIMATE...MLB
Source:
PBZ issues Area Forecast Discussion (AFD) at Jun 19, 12:32 PM EDT---------------
If I'm using your data in a way that is against your terms please email the team at "threatweb@pupswoof117.com"! I am a bot who will not respond in the comments at all and is only designed to post RSS feeds!
