Doorman

https://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=qpfhsd WPC disco ...Ohio Valley, Mid-Atlantic, Northeast... Day 3... A fast moving shortwave dropping southeast upstream of the broad trough across the eastern CONUS will amplify as it shifts towards the Ohio Valley Friday morning, and then maintain its amplitude during its trajectory eastward across the Mid-Atlantic. The flow is fast, and the shortwave is of modest intensity, but it will be efficiently topped by a potent 170+kt jet streak diving through the trough to enhance deep layer ascent. At the same time, a cold front will be making its way eastward from the Great Lakes to the Mid-Atlantic states, and it is possible the associated fgen along this front could be enhanced by the upper jet streak pivoting overhead. This will likely enhance ascent and will result in a surface low pressure developing near the Carolinas and then racing east-northeast into Saturday /D4/. PWs downstream of the best ascent are expected to be modest within the generally zonal and fast flow, although some enhancement towards +1 sigma may surge northward into VA as reflected by the NAEFS ensemble tables, but this will likely be dependent on the intensity of the surface low to drive more robust theta-e advection northward. The GFS/ECMWF and their associated ensemble clusters have trended weaker/farther southeast today, but the CMC and its ensemble remain more intense and closer to the coast. The threat for heavy snow appears to be a little lower than from previous model cycles, but uncertainty is still high, and regional soundings indicate support for high SLR snow due to a cold column and SREF DGZ depth probabilities for 100mb reaching 10-30%. WPC probabilities for more than 4 inches of snow on D3 are modest but expansive, reaching 10-30% in a west-to-east oriented swath from eastern Indiana through Long Island, although probabilities have decreased today. The exception is along the WV Appalachians where colder temperatures and some upslope flow should result in efficient snowfall accumulations, and WPC probabilities for 4+ inches are above 50% in this area. OPC 72hr prog

Excessive Rainfall DiscussionNWS Weather Prediction Center College Park MD1154 AM EDT Thu Sep 28 2023Day 1Valid 16Z Thu Sep 28 2023 - 12Z Fri Sep 29 2023...A SLIGHT RISK OF EXCESSIVE RAINFALL IS IN EFFECT OVER PORTIONSOF THE MID-ATLANTIC AND NORTHEAST......16Z Update...In coordination with the local WFO offices in Mount Holly andUpton, have upgraded the D1 ERO to a Slight Risk given the trendsin short term guidance in terms of placement and magnitude ofheavy rainfall this evening. General synoptic scale patternremains fairly similar to previous forecast package, but moreemphasis on heavy rain potential has arose given the signals onthe latest ensemble means and deterministic QPF distribution. 12zHREF neighborhood probabilities of >1" and >2" totals acrossnorthern and central NJ, as well as the NYC metro into thesouthern Catskills was sufficient to upgrade the area to the SLGTrisk. There is still some discrepancy on the exact placement ofthe heaviest QPF footprint, however the highly anomalous u-vectorwind fields across northern NJ and adjacent areas are allprevalent across all guidance which would generate a robustupslope component typically found in these types of heavy rainevents. Convective potential is still on the low side, butnon-zero given the theta-E advection regime likely overnight intoearly tomorrow morning as indicated by all deterministic, globalor hi-res base. Total QPF between 1-2" with locally as high as 4"are being depicted within the HREF blended mean QPF which onlylends credence to the higher potential with the SLGT. Main areasof concern will be the higher terrain in NNJ and southern NYstate, as well as the urban areas in-of NYC/Newark/Jersey City. https://www.wpc.ncep.noaa.gov/index.shtml#page=ero

big bump upward ATM

right click on the link below for sat loop .... https://weather.cod.edu/satrad/?parms=subregional-Mid_Atlantic-natcolor-24-1-100-1&checked=map&colorbar=undefined

https://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=qpfhsd WPC disco Probabilistic Heavy Snow and Icing Discussion NWS Weather Prediction Center College Park MD 402 PM EDT Sun Mar 12 2023 Valid 00Z Mon Mar 13 2023 - 00Z Thu Mar 16 2023 The heaviest snow will likely occur in the interior northeast terrain including the Adirondacks, Catskills, Greens, Berkshires, Worcester Hills, Monadnocks, and Whites where WPC probabilities for 6 inches are above 80% on D2, and reach 50-80% for 12 inches in these same areas. In the valleys, snow totals will likely be less, but intense ascent could still prevent extreme shadowing on the e/ne flow, and WPC probabilities for 6+ inches are above 50% even in the lower elevations all the way up the coast of Maine despite that area being impinged upon by drier air and being more removed from the low center as it moves east instead of northeast late. For the I-95 corridor, there is good potential for a period of heavy snow to develop on the back side of the system near the coastal front, and while WPC probabilities for NY to Boston are pretty low for 2-4 inches, the guidance has trended a bit more aggressively for this area, and there are several members in the WSE plumes that suggest heavy accumulations even to the coast. While confidence in major impacts and heavy snow accumulations is greatest inland across the higher terrain, the potential still exists for a significant snowstorm for NYC to Boston as well. THE DARTBOARD

even if it isn't in your backyard..... those red colors (totals) still have to grab at ya, in the month of March

SOGGY

Frank Gorshin eat your heart out.... https://digital.weather.gov/

https://www.wpc.ncep.noaa.gov/#

Upton NWS disco LONG TERM /THURSDAY THROUGH MONDAY/... No changes were made to the long term forecast Thursday through next Monday. Another piece of PAC energy sets its eyes on the area late in the week into the weekend. The operational global models are in very good agreement in taking this energy and closing off an upper low in the vicinity of the the Northern Plains and/or Upper Midwest Thursday night into Friday, then diving the system ESE and off the Mid Atlantic coast Saturday. This will allow for a secondary low to form along the coast as the upper forcing approaches. Greatest uncertainty lies where the secondary forms. GEFs is the northernmost of the ensemble means and has good clustering just south of Long Island, however, the EPS and GEPs means are much farther south and also support their operations runs. NBM wind field, which was closely followed, reflects a track south of the forecast area. Like so many southern branch systems this year, the track and lack of available cold air, has resulted more often in liquid than frozen precipitation events. This event is no different. In addition, unlike the last 2 systems, there is no block across eastern Canada with cold air source bleeding cold air south across New England. Thus, this looks to be a mainly rain event with a rain/snow mix possible on the backside Saturday night. Prior to that time, offshore low pressure and a northerly flow from eastern Canada into New England will result in temperatures near normal with highs in the 40s and lows in the 20s inland and 30s at the coast. High pressure to the west slowly builds into Thursday until weakening and moving offshore Friday ahead of the aforementioned coastal low. While it will still be breezy on Thursday, gusts should be weaker than Tuesday and Wednesday, generally 20-25 mph. Winds weaken further for Friday with high pressure over the area. Over the weekend, temperatures will depend on the exact track of the low, but subtle departures are forecast from the mid week period. It should be noted that NBM probabilities for seeing greater than 1 inch of liquid equivalent in 24h for the potential weekend system have held fallen a bit to 15 to 30 percent percent. For 2 inches, it remains generally under 5 percent. https://forecast.weather.gov/product.php?site=OKX&issuedby=OKX&product=AFD&format=CI&version=1&glossary=1&highlight=off

https://digital.weather.gov/

COD MET meso-floater small scan mode https://weather.cod.edu/satrad/?parms=meso-meso1-02-96-1-100-1&checked=map&colorbar=undefined