Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 221113 AFDOKX Area Forecast Discussion National Weather Service New York NY 713 AM EDT Wed Mar 22 2017 .SYNOPSIS... A cold front will move across early this morning. High pressure then starts building from the Great Lakes, moving more into the region tonight into Thursday. The high moves offshore Thursday night. A warm front passes Friday, followed by a cold front Saturday. The front remains south of the area as high pressure builds to the north over the weekend. Waves of low pressure impact the area early next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Jet stream dives south of the region today with cold air advection. Model fields of 850mb temperatures drop to near -15 to -16 degrees C. A cold front moves across early this morning with a tightening pressure gradient between a low moving towards Nova Scotia and a Canadian high moving into the Great Lakes. This combined with daytime mixing will allow for most top of the mixed layer winds to be realized. A windy and cold day will be the result. Wind gusts are expected to reach near 31mph sustained and near 46mph gusts for quite a few locations. A wind advisory is in place for the entire region through the day. Daytime highs stay in the 30s which will be well below normal. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/... Dry and cold through the period. Jet stream still south of the region this evening with more of a ridging trend thereafter as the jet starts to move back north. Winds starts to taper down tonight, with Long Island/NYC still seeing some higher gusts until 8pm. Wind advisory still in effect early part of this evening (6-8pm) for NYC and Long Island. The pressure gradient thereafter starts to lower with the closer proximity of high pressure building in from the NW. Lows tonight and highs Thursday used a blend of MAV/MET/GMOS. Well below normal values with lows tonight in the lower teens to lower 20s and highs Thursday in the upper 30s to lower 40s. Thought for the lows tonight, the radiational cooling will be partially mitigated due to mixing with winds in the boundary layer. Wind chills drop into the single digits for most locations. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Unsettled weather through much of this time frame. Model details remain uncertain, but chances for wet weather look likely through the period. A warm front passes Friday as high pressure departs to the east. Generally light precip is expected as the warm front moves through, certainly not a wash out, or significant event. A cold front will likely approach from the north as a ridge of high pressure moves across central canada, pushing the front southward. The front sags just to the south late Saturday, and will remain there for several days. Once again, some wet weather is possible Saturday and Saturday night as the front moves through, but not a wash out. Then, attention turns toward upstream trough and low pressure as it approaches from the west Sunday and Monday. Looks like a good chance for rain, or a wintry mix across the interior, at times. This trough passes, with yet another one on its heels Tuesday. More wet weather expected by that time. Temperatures will remain on the cool side, especially once the front passes to the south late Saturday. Near normal temps are expected Friday, with slightly above normal readings for Saturday. Thereafter, readings in the 40s during the day, with 30s at night are forecast as the local area remains north, or on the cool side of the front. && .AVIATION /11Z WEDNESDAY THROUGH SUNDAY/... Canadian high pressure is building into the region. VFR through the TAF period. NW winds 15-20KT with gusts up to 30KT into late morning. The strongest winds will occur from 14Z-23Z when NW winds will be sustained near 25KT with gusts up to 35KT. There could be a period between 15Z-20Z when gusts could reach 40KT. Gusts begin to drop off after sunset and diminish after midnight. NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/ KJFK TAF Comments: Wind gusts could occasionally be stronger than forecast. KLGA TAF Comments: Wind gusts could occasionally be stronger than forecast. KEWR TAF Comments: Wind gusts could occasionally be stronger than forecast. The afternoon KEWR haze potential forecast is GREEN...which implies slant range visibility 7SM or greater outside of cloud. KTEB TAF Comments: Wind gusts could occasionally be stronger than forecast. KHPN TAF Comments: Wind gusts could occasionally be stronger than forecast. KISP TAF Comments: Wind gusts could occasionally be stronger than forecast. .OUTLOOK FOR 00z THURSDAY THROUGH SUNDAY... .Wed...VFR. NW Gusts 30-35 kt. .Thursday..VFR. .Friday...CHC PM shra/mvfr. SW gusts 25 kt. .Saturday...Mainly VFR. .Sunday...MVFR/IFR and rain. E gusts 20-25 kt. && .MARINE... Gales expected to develop shortly after daybreak with the cold frontal passage. Efficient mixing between colder air aloft and relatively warmer sea surface will easily allow for gusts in the 35-40 kt range. This will start to decrease tonight from west to east. Gale warning remains until 06Z Thursday. SCA remains likely thereafter late tonight into early Thursday before all waters go below SCA for the rest of Thursday. High pressure moves across the waters Thursday night, and passes well to the east Friday. Winds diminish during this time, but begin to increase from the SW later Friday into Friday night. A cold front approaches from the north Saturday, and settles near or just south of the waters Saturday night into Sunday. Winds diminish, and turn toward the E/NE. Speeds increase yet again Sunday as high pressure builds well to the north. && .FIRE WEATHER... NW winds of 15-30 mph with gusts 35-50 mph and min RH dropping to near 20 to 25 percent should help dry fine fuels across the snow barren ground. This will enhance the threat for brush fire spread in those areas today. Winds are lighter but similar RH values are expected for Thursday. && .HYDROLOGY... Unsettled weather from this weekend through early next week may result in an inch or more of precipitation. However, this would occur over a prolonged period and would be intermittent, so no hydrologic concerns are anticipated. && .CLIMATE... The following are record low temperatures for Thursday March 23, 2017 along with the forecast low temperatures. Record Low Temperature Forecast Low Temperature ---------------------- ------------------------ Central Park........12 (1875) 21 LaGuardia...........20 (1959) 22 Kennedy.............20 (1959) 21 Islip...............15 (2004) 18 Newark..............13 (1934) 19 Bridgeport..........19 (2004) 19 && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Wind Advisory until 6 PM EDT this evening for CTZ005>012. NY...Wind Advisory until 8 PM EDT this evening for NYZ072>075- 078>081-176>179. Wind Advisory until 6 PM EDT this evening for NYZ067>071. NJ...Wind Advisory until 6 PM EDT this evening for NJZ002-004-006- 103>108. MARINE...Gale Warning until 2 AM EDT Thursday for ANZ330-335-338-340- 345-350-353-355. && $$ SYNOPSIS...JM/PW NEAR TERM...JM SHORT TERM...JM LONG TERM...PW AVIATION...CB MARINE...JM/PW FIRE WEATHER... HYDROLOGY...JM/PW CLIMATE... is the U.S. government's official web portal to all federal, state and local government web resources and services.