Area Forecast Discussion
Issued by NWS State College, PA

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KCTP 271536 AFDCTP Area Forecast Discussion National Weather Service State College PA 1136 AM EDT FRI MAY 27 2016 .SYNOPSIS... A ridge of high pressure over the western Atlantic will bring warm and increasingly humid conditions to the region into the holiday weekend. Cooler and showery weather may arrive for Memorial Day. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
After a warm and tranquil morning, diurnal heating of moist airmass should yield sct pm, pulse-type convection. NCAR ensemble data indicating CAPEs surging to arnd 2000 J/kg, which could support locally isold strong wgusts/hail in best cells. However, wind fields and deep lyr shear are weak, indicating organized svr wx is unlikely. Although aftn Pops are blw 50 pct, what rain does fall could be locally heavy, due to slow storm motion and high PWATs. Convection-allowing mdls (HRRR) show this potential with highly localized amts in excess of around 2 inches possible in just an hour or so. Mdl 850mb temps close to 16C are supportive of max temps today ranging from the l80s ovr the highest terrain, to nr 90F over the Susq Valley.
-- End Changed Discussion --
&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... Diurnally-driven convection should fall apart with loss of heating this evening. Partly cloudy skies and light wind could yield patchy fog tonight where ground is wet from pm showers. High dewpoints will lead to another very warm night with min temps in the mid 60s over much of the area. Subtropical ridge builds nwrd into Pa on Sat with 500mb height anomalies reaching 2SD across southeast Pa. The assoc warm temps aloft should suppress convection across the se counties Sat aftn. However, sct diurnal tsra again appear likely across the nw half of the state. Thermodynamic/kinematic profiles appear similar to Friday, with moderate CAPE and weak shear suggesting pulse-type convection and low risk of organized svr wx. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Summertime upper level ridge over the Mid Atlantic and Northeast states is forecast to peak around 29/00z with above normal heights returning to normal by early next week. Temperatures should follow a similar trajectory with positive temp departures trending modestly lower/toward climatology into the first week of June. The tropical disturbance /Invest AL912016/ approaching the Southeast U.S. coast will add additional moisture to an already humid/unstable airmass in place through Memorial day weekend. Some interaction between the tropical disturbance and mid latitude trough crossing the Central Appalachians likely favors the greatest pcpn risk/potential pcpn coverage Sunday night into Memorial Day (Monday) with a decreasing chance for rain into Tuesday. Deterministic and ensemble guidance are in broad agreement in a dry period of weather from Tuesday into Wednesday before pcpn risk gradually increases into the second half of next week. Heights are forecast to rise a bit around the end of the period before the large scale pattern slowly shifts toward a western ridge/eastern trough configuration by June 5th as depicted by the 27/00z NAEFS and ECENS. && .AVIATION /16Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
Ridge of high pressure remains in control keeping a summertime weather pattern in place. VFR conditions will dominate much of the remainder of the day. Though enough moisture/cape in place to generate sct pulse-type thunderstorms with locally gusty winds in mid/late afternoon across mainly eastern half of cwa. Did mention late-day VCTS in Susq Valley in TAFS. Any flight restrictions should be mainly 15-30 minutes of mvfr cigs and vsbys...though very brief ifr conditions are possible. Vsby reductions to MVFR more likely tonight with humidity increasing...with a few areas of IFR fog mainly confined to places that receive rain today. OUTLOOK... Sat...Early am low cigs/vsby possible. Isold pm tsra impacts. Sun...Sct pm tsra impacts possible...mainly nw half. Mon...Sct pm tsra impacts possible...mainly se half. Tue...No sig wx.
-- End Changed Discussion --
&& .CTP WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Fitzgerald/Lambert NEAR TERM...Lambert SHORT TERM...Fitzgerald LONG TERM...Steinbugl AVIATION...Lambert/RXR

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.