495 FXUS61 KALY 301049 AFDALY Area Forecast Discussion National Weather Service Albany NY 649 AM EDT Wed Aug 30 2017 .SYNOPSIS... Weak high pressure will build into the region today, resulting in gradual clearing and warming temperatures. A cold front approaching from southeast Canada will sweep across the area and bring a chance of showers and a few thunderstorms to the region on Thursday. Behind the front, a cool fall-like air mass and breezy conditions will filter in. Cool temperatures will linger into the first half of the upcoming weekend. && .NEAR TERM /THROUGH TONIGHT/... As of 634 AM EDT...Any remaining showers across the southeast portion of the area have ended, with clouds gradually clearing from the Hudson Valley westward at this time. Due to the clearing, patchy fog has developed in sheltered valley locations in the Mohawk/Schoharie Valleys, western Catskills, and western Dacks. Ocean storm located well south of southern New England and heading farther out to sea rapidly. Good subsidence in wake of this system will result in gradually clearing skies across eastern New York and western New England this morning into early afternoon. Temperatures will respond to the increase in sunshine after a rather cool and cloudy day Tuesday. High temps should bounce back and reach the upper 60s to mid 70s by late this afternoon. Generally dry weather expected to continue through tonight, however a fast-moving cold front approaching from southeast Canada may trigger a few showers across the western Adirondacks before daybreak Thursday. Low temps should be close to normal, as clouds gradually increase late after a mainly clear start to the night. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... The aforementioned cold front will be already positioned across the Adirondacks at the start of the day, and will quickly sweep southeast across the rest of the region Thursday morning into the afternoon. Models indicating not much moisture or instability ahead of the front, with limited dynamics as well with the associated upper trough expected to lag well to the north across Quebec. Some minor instability may develop just ahead of the front from about the Mohawk Valley and Capital District southward, so will mention isolated thunderstorms along with expected mainly scattered coverage of showers. Forecast SBCAPE values of only a few hundred to around 500 J/Kg will result in general thunderstorms, as there will not be enough buoyancy/moisture for more robust storms to develop. Drier and cooler air will start to move in Thursday night, with any showers or storms ending by early evening. An unseasonably cool air mass will quickly filter in with 850 mb temperature anomalies of -2 to -3 STDEV forecast by Friday morning. The center of an upper low will settle in towards extreme SE Quebec, and will drive a short wave southward into our region as well. A fairly strong pressure gradient for late August will allow for winds to remain breeze through Thursday night and into Friday. So it will feel quite cool with low temps forecast in the mid 30 to mid 40s across the region along with a breeze. High pressure will start to ridge eastward across western/central NY on Friday, although there will still be a cool northwest flow and continued anomalously cold air aloft. So temperatures are expected to be well below normal with only upper 50s to mid 60s for highs across much of the region. It will feel very fall-like with a continued northwest breeze. The high then looks to move overhead Friday night, which will result in winds diminishing and continued cool temperatures. With calmer winds, there will be the potential for some frost across parts of the western/southern Adirondacks and southern Green Mountains of VT as temperatures drop into the mid 30s with mainly clear skies. It will be chilly elsewhere as well with upper 30s to mid 40s. && .LONG TERM /SATURDAY THROUGH TUESDAY/... After an extended period of mainly dry weather some needed rainfall is expected as we head into Labor day weekend. Below normal temperatures are expected as we start September with them forecast to moderate to seasonable levels for early next week. The dissipated remnants of Harvey are expected to be pick up and absorbed by a short wave as it moves across the Great Lakes region and across the Northeast this weekend. Another short wave is expected to approach and move across the region resulting in the development of an upper low near Hudson's Bay and a broad longwave trough early next week. The weather is then expected to be unsettled as fronts associated with short waves rotating about the upper low approach and move across the region. Fair weather is expected Saturday with increasing clouds as some ridging is induced across the region ahead of the approaching short wave. With a chilly start to the day highs are expected to run 5 to 10 degrees below normal. Chances for showers increase Saturday night especially late and continue on Sunday. At this time have kept pops in the high chance range as there are some issues with the timing of individual features. As confidence increases so will pop forecast. Moderating temperatures Monday in southwest flow ahead of an approaching cold front for Labor Day. Along with the seasonable temperatures will come some chances for showers mainly north and west of the Capital District. Another, stronger, cold front will be on the approach Tuesday which will bring a continued threat for showers. There are still difference amongst the guidance regarding strength of the system and the timing of the cold front passage. As it looks at the time Tuesday should be another day of seasonable temperatures across most of the area with southwest flow. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... The area of low pressure which passed south of Long Island and Cape Cod will continue to move northeastward out to sea and away from the region today. VFR conditions with scattered clouds are expected today. A cold front will be on the approach from the northwest late and clouds will be in the increase ahead of it. Winds will be light generally from the west to northwest at less than 10 knots. Winds will diminish this evening becoming light and variable to calm. Outlook... Thursday: Moderate Operational Impact. Chance of SHRA and a slight chance of TSRA. Thursday Night-Saturday: No Operational Impact. NO SIG WX. Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: Moderate Operational Impact. Chance of SHRA. && .FIRE WEATHER... Weak high pressure will build into the region today, resulting in gradual clearing and warming temperatures. A cold front approaching from southeast Canada will sweep across the area and bring a chance of showers and a few thunderstorms to the region on Thursday. Behind the front, a cool fall-like air mass and breezy conditions will filter in. Cool temperatures will linger into the first half of the upcoming weekend. Minimum relative humidity values will be around 40 to 50 percent this afternoon, increasing to maximum values of between 90 and 100 percent tonight. Minimum RH values on Thursday will be around 45 to 60 percent. Winds today will be northwest around 5 to 10 mph, becoming westerly tonight. Winds on Thursday will shift to the northwest behind a cold front and increase to 10 to 15 mph with gusts around 20 mph. && .HYDROLOGY... Dry conditions are expected today and tonight, as weak high pressure builds in. A cold front will bring scattered showers and a few thunderstorms on Thursday, but basin average amounts will generally be fairly light and will have a limited (if any) impact on rivers and streams. Dry weather will then return behind the front for Friday and most of Saturday. The next chance of rainfall arrives Saturday night into Sunday. By then, rain will be needed as it will have been over a week since the last widespread measurable rainfall. With limited amounts of rainfall expected, river and stream levels will remain fairly steady through the weekend. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .EQUIPMENT... The KENX radar is expected to be down through at least September 1st for the bull gear to be replaced. Technicians started the work on the bull gear replacement Saturday August 26. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...JPV NEAR TERM...JPV SHORT TERM...JPV LONG TERM...IAA AVIATION...IAA FIRE WEATHER...JPV HYDROLOGY...Frugis/JPV EQUIPMENT...