Area Forecast Discussion
Issued by NWS State College, PA
Issued by NWS State College, PA
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824 FXUS61 KCTP 270229 AFDCTP Area Forecast Discussion National Weather Service State College PA 1029 PM EDT Sun Jul 26 2026 .WHAT HAS CHANGED... Threat for isolated strong storms with heavy rainfall has ended in the Lower Susquehanna Valley && .KEY MESSAGES... 1) Severe thunderstorms capable of damaging winds and heavy to potentially excessive rainfall are possible Monday and Tuesday && .DISCUSSION... A couple of persistent, slow moving T-storms pushed both severe and flash flooding warning limits late this evening in the Lower Susquehanna Valley. Upper shortwave progressing through the Mid Atlantic could linger isolated convection early into the overnight hours. Areas of fog should expand in coverage through predawn into daybreak early Monday morning. KEY MESSAGE 1: Severe thunderstorms capable of damaging winds and heavy rainfall are possible Monday and Tuesday There is still some uncertainty regarding the coverage of storms during the day on Monday as upper level forcing is expected to remain weak. We should see at least scattered thunderstorm development during the afternoon as modest instability develops, but shear will remain weak. The severe threat appears to be low, but a few strong to severe wind gusts will be possible with any stronger storms. Some models show an MCS diving south from the Great Lakes Monday night which could impact western portions of the area, but confidence is low on timing and placement of this feature. Tuesday will likely see the most widespread showers and thunderstorms of the week as a potent shortwave approaches from the west and its associated surface low tracks over the region. Showers and storms will likely be ongoing across parts of Central PA Tuesday morning and should continue through the rest of the day. The potential for severe weather remains uncertain as it will depend on much we are able to destabilize behind the morning showers and storms. SPC has areas roughly along and south of I-80 in a marginal risk for severe weather and they have included far southern portions of the area in a slight risk. Heavy rain will also be a concern Monday evening into Tuesday with any storms that develop as PWAT values will climb to around 1.8 inches. Storms will be very efficient rainfall producers and areas that see repeated rounds of thunderstorms may see some flash flooding concerns develop. WPC has placed nearly all of Central PA in a marginal risk for excessive rainfall for both Monday and Tuesday. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... Shower/thunderstorm activity will gradually diminish this evening along the north-south moisture/convergence boundary near KIPT/KMDT/KLNS, with largely rain-free conditions elsewhere through tonight. Localized MVFR-IFR restrictions would be possible underneath these cells, though confidence in these pulse-y cells being overhead at KIPT/KMDT/KLNS is too low for TAF inclusion (<30% chance). Otherwise, patchy fog is expected overnight given light/variable winds and the gradual uptrend in low-level moisture over the past few days, with highest confidence in overnight fog currently for KBFD. Patchy morning fog will give way to primarily VFR conditions during the daytime on Monday, with scattered showers/storms ahead of a shortwave over the Great Lakes & Ohio Valley bringing another chance for localized MVFR-IFR restrictions. Meager deep-layer wind shear (0-6 km shear around 15 kts) will support pulse-y cells/clusters, with typical summertime moisture (PWATs of around 1-1.5") and a well-mixed boundary layer (0-3 km lapse rates of around 8-9 C/km) driving the chance for visibility restrictions and localized wind gusts. Chances for TSRA at any one terminal is around 30% at this time, given the broadly supportive yet diffuse lifting mechanism at play. Outlook... Tue...Restrictions likely with scattered -SHRA/-TSRA. Wed-Thu...Restrictions possible as -SHRA/-TSRA becomes less numerous. Patchy overnight fog possible. Fri...VFR favored with slight chance for -SHRA. Patchy overnight fog possible. && .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ WHAT HAS CHANGED...Steinbugl/Bauco KEY MESSAGES...Steinbugl/Bauco DISCUSSION...Lambert/Bauco AVIATION...Teare