Sunrise 6:10 AM   Sunset 8:41 PM Moonrise 2:05 PM   Moonset 2:26 AM

  Print   HELP   Reset   Save   Recall  New

FXUS61 KPBZ 171431 AFDPBZ

Area Forecast Discussion National Weather Service Pittsburgh PA 1031 AM EDT Fri May 17 2024

SYNOPSIS
Unsettled weather returns today through Saturday with periodic showers and a few thunderstorms. Near to above normal temperatures will continue.

NEAR TERM /UNTIL 6 PM THIS EVENING/
KEY MESSAGES:

- Showers and a few thunderstorms will continue today with the passage of a weak trough.
- Localized heavy rainfall totals and water issues are possible.
- Near-normal high temperatures and above-normal low temperatures can be expected.
_____________________________________________________________

Showers with a couple of embedded thunderstorms continue to cross the region this morning with a relatively weak mid-level trough and a nearly nonexistent surface reflection. Nearly saturated low-level profiles and precipitable water values of 1.3 to 1.4 inches have led to locally efficient rainfall, with a few radar-estimated totals above an inch in eastern Ohio.

Although SBCAPE may modestly increase into the 600-750 J/kg range this afternoon, the overall lack of shear will keep any severe concerns to a minimum. However, conditions favorable for locally heavy rainfall will continue. Coverage will become a bit spotter and more convective this afternoon, but isolated high water issues are still possible if any one location gets hit with multiple rounds of rain.

SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/
KEY MESSAGES:

- Shower chances continue along with above normal temperatures.
_______________________________________________

Upper troughing still transitioning across the region will maintain shower chances on Saturday. Favored left entrance region jet dynamics lie closer south and east of PGH, so have maintained higher PoPs across the southern CWA Again, NBM 24-hour half- inch probabilities remain below 50 percent with the same north- to- south gradient. Severe threat remains very low as well.

Diurnal temperature spreads will be fairly low given the expected clouds and rain, with near-normal maximums but above-normal minimums.

LONG TERM /SUNDAY THROUGH THURSDAY/
KEY MESSAGES:

- Ridging should result in dry and warmer weather Sunday and into next week.
- Rain chances return for Wednesday and Thursday.
____________________________________________________________

The earlier trend towards a more southerly track for the main shortwave trough on Sunday continues in the recent guidance. This does lead to generally low PoPs on that day, focused on areas south of Pittsburgh where moist easterly flow lingers during the morning.

Ensembles then seem to be in decent agreement in keeping this trough/upper low near or just off the southeast CONUS coast, while slowly rising 500mb heights take control over the Upper Ohio Valley.
This points to mainly dry weather from Sunday night through Tuesday, with increasingly above-normal temperatures through early next week.

The next shortwave trough then drives across the Upper Mississippi Valley towards the Great Lakes during the midweek period. Model cluster guidance shows strength and timing differences with this, which point to various scenarios for precipitation amounts and severe weather chances. In any case, PoPs topping in in the likely range and muted, but still warm high temperatures looks to be the forecast of least regret at this time.

AVIATION /14Z FRIDAY THROUGH TUESDAY/
Rain showers with periods of embedded thunder are reducing visibility to MVFR at times this morning across eastern OH and into the WV Panhandle. Latest guidance and upstream observations suggest a continued slowing trend of cig falls this morning, with the most pronounced drops in cigs most likely to arrive after precipitation onset and highest MVFR probabilities for BVI, FKL, DUJ of 60-80% with slightly lower probabilities further south and east. Guidance show most sites dropping to low VFR or high MVFR in morning showers, though temporary drops in vis in heavier showers are possible and denoted in tempo groups. Some cig recovery is expected into the early afternoon with breaks in the rain shield save FKL and DUJ which are favored to remain MVFR.

Rain coverage should taper off and become more isolated/scattered this afternoon, though with that we'll see increasing thunder probabilities. Confidence in coverage and exact timing remains low at this point, but any sites that see a heavier shower/thunderstorm could experience a brief drop in cig and vis. Some fog formation is possible toward daybreak Saturday with lingering low level moisture from earlier rainfall.

MVFR cig restrictions will favor FKL/DUJ after 18z, with probabilities increasing areawide after 06z Saturday.

Outlook
Upper trough passage to the south Saturday will maintain shra/tstm chances focused south of KPIT, with varying degrees of restriction potential. VFR and dry weather become high probabilities Sunday into Monday under the influence of high pressure.

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

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Cleveland, OH,