Area Forecast Discussion
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FXUS61 KCTP 281248
Area Forecast Discussion
National Weather Service State College PA
848 AM EDT SAT MAY 28 2016
A ridge of high pressure will remain centered over Pa today and
Sunday. A trough of low pressure will push across the region late
Sunday into early Monday. High pressure will build into the
region early next week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Subtropical ridge centered off the e coast will expand nwwd into
Pa today, with 500mb height anomalies reaching 2SD across
southeast Pa. The assoc warm temps aloft should suppress
convection across the se counties this aftn. However, sct diurnal
tsra appear likely across the remainder of central Pa.
Thermodynamic/kinematic profiles appear very similar to those of
Friday, with moderate sfc-based cape of 1500-2500 j/kg and weak
shear, suggesting pulse-type convection and a low risk of
organized svr wx. Although most locations will likely miss out on
rainfall, slow moving tsra will likely produce localized rain amts
of arnd 2 inches in a few spots, as implied by ncar high res
Ens mean 8h temps near or slightly higher than those of Friday, so
have added a degree or two to max temps, which should range from
the m80s ovr the Allegheny Mtns, to arnd 90F across the Susq
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
Diurnally-driven convection should rapidly die out after sunset.
Focus will then shift to potential of patchy fog in those
locations that receive rain later today.
Increasing high and mid lvl cloudiness expected Sunday in advance
of shortwave lifting out of the midwest, which should hold temps
down a bit. Superblend max temps ranging from the u70s ovr the
Alleghenies to l80s Susq Valley. As lg scale forcing ramps up
ahead of shortwave, expect an increasing chc of pm tsra, mainly
across the western counties.
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Although tropical depression is progged to remain well south of
Pa, a plume of tropical moisture lifting up the mid atl coast,
combined with approach of mid lvl shortwave from the west, could
produce some locally sig rainfall Sun night across eastern Pa.
GEFS and oper GFS/EC all indicate the potential of 1+ inches of
rain Sunday night across our se counties. Some uncertainty with
regards to how fast shortwave and assoc weak cold front clear the
area Monday. Trend has been for a more progressive shortwave
resulting in a dry Memorial Day. However, the slower 00Z EC
solution still suggesting showery wx could linger across the se
half of the state.
Deterministic and ensemble guidance are in broad agreement in a
period of fair/warm weather from Tuesday into Wednesday before
pcpn risk gradually increases late in the week ahead of 5h trof
and assoc cold front approaching from the Grt Lks.
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
Low conditions at the 3 eastern sites just after sunrise...but
improving fast now.
Ridge of high pressure remains in control, keeping a summertime
weather pattern in place.
Vsby reductions to MVFR likely around sunrise with humidity
continuing to gradually increase, with a few areas of IFR fog
mainly confined to places that receive rain Fri aft. Any reducing
conditions will lift between 12Z to 14Z.
Ridge will suppress convection and keep cumulus thin in the
southeast this afternoon. Chance for showers and thunderstorms
will be confined mainly to NW half. Overall conditions will remain
VFR, with local reductions in sct convection.
Sun...Sct afternoon tsra impacts...mainly nw half.
Sun night...Reductions likely mainly se half in showers/tstms.
Mon...Sct tsra impacts...mainly se half.
Tue and Wed...No sig wx.