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SPC at 145PM EDT. No guarantee for for me in Wantage we may miss the first batch developing east northeast from vcnty Brodheadsville in ne PA. storm looks impressive at 153P. This should be the batch to watch. again, no guarantees. Hope this works out well. https://www.spc.noaa.gov/products/md/md1313.html Mesoscale Discussion 1313 NWS Storm Prediction Center Norman OK 1245 PM CDT Wed Jul 22 2020 Areas affected...portions of eastern PA...NJ...southern NY and southern New England Concerning...Severe potential...Watch possible Valid 221745Z - 221945Z Probability of Watch Issuance...60 percent SUMMARY...Scattered thunderstorms will increase in coverage and intensity through the afternoon. Strong, locally damaging gusts will be possible with these storms into this evening. DISCUSSION...A broad area of deepening cumulus continues to develop across portions of eastern PA/NJ northeastward into southern New England ahead of a shortwave vorticity max. At the surface, a warm front extends from central NY east/southeast into CT/RI. South of the front, surface dewpoints are mainly in the 70s F and strong heating has allowed temperatures to warm into the mid to upper 80s F. As a result, a tongue of MLCAPE from 500-1500 J/kg resides from eastern PA and NJ northward into southern NY and western CT. The warm front should progress northward a bit more through the afternoon and at least weak destabilization is expected as far north as southern VT/NH into western/central MA. In addition to weak to moderate instability, moderate deep shear resides over the region, and effective bulk shear around 35-45 kt should overspread the entire MCD area by late afternoon. Some uncertainty with regards to convection initiation remains, largely due to weak forcing across the area. A vorticity max further east near Lakes Erie/Ontario should spread eastward with time, but initial convective development may be largely driven by diurnal processes, especially over southern portions of the MCD area from far southern NY/Long Island southward into NJ. Nevertheless, the overall environment should support organized cells and clusters, once they develop. Midlevel lapse rates will remain modest, but strong heating has resulted in steep low level lapse rates south of the warm front, and PW values greater than 1.75 inches will further aid in strong downburst potential. While timing of convection remains a bit uncertainty, at least sporadic instances of severe gusts and locally damaging winds are expected into the evening hours, and a watch may be needed this afternoon, within the next few hours. ..Leitman/Hart.. 07/22/2020

Also, fwiw... the primary line had previously been slated by primary USA guidance in the 5-9P slot for our area. Am not too worried, yet. New cell near ABE and it looks to me like central PA activity is developing enewd. I may be off line for a couple of hours. Ride it out a little while longer and follow NWS/SPC discussions and your own observations of surface convergence, and cu field pooling-development. Thanks.

Very helpful to know gentlemen... I tried the link provided this morning, a couple of days ago and no luck. So, am glad it just wasn't my own operator error. That said...also helpful to know NBE performance and... good thing that it improved on MEX because we're in a statistically persistent pattern of warmer than climate normal. I'd be really disturbed if NBE didn't improve on MEX. Also, had seen EC MOS in its more primative non gridded stage prior to March 2018 retirement, within NWS. Sharing International model guidance is relationships, benefits to countries etc. NWS I think incorporates the MOS into some of their products, if forecasters elect to init with the base blended statistical data.

Quickly reevaluated with latest guidance (RGEM, GFS, NAM, NAM3K HRRR and last nights ARW 1 and 2). Please point out what I'm missing. I could be missing something. Otherwise, I'm seeing poor 12z model radar init for 16z. and wherever I see it has something, the development is northeast toward virtually all of our NYC forum by late afternoon. 16z S wind IPT area with dew points in the 70s in e PA/NJ/NY, plus cu fields from ne PA into nw NJ suggest to me to look for further developement northeastward in this cu field and eventual big storms by 5P. I could be wrong... so no guarantee but that's what I see from a quick glance at surface, cu fields and modeling. Big storm suggestion is the anvil blowoff in the little cell vicinity York PA past 45 min.

TCU w and ne of Wantage around 1220... tiny cells just e and ne of NYC. Line growing central PA. Will review. 86/73 here in Wantage 1230P.

Thanks UOFMIAMI and BLUEWAVE for your replies. Couldn't get the MOS to work earlier, but now good with your link and also hadn't seen the transition announcement. Thanks to you both. I'll be checking the NBM against GFS MEX MOS in some critical situations. offline til about 1230P. Walt 1029A/22

Quick question: Am a little frustrated with MDL not posting MOS since 7/6 and I know NWS wants buy in on the NBM and is ready to discontinue, but myself, I like MOS as an idea of concerns. Is anyone able to acquire the GFS extended statistical guidance for locations in NJ and NYC... (not ALB). Just point me in the right direction. Thanks much, Walt

Onward: Friday: may still have some showers and isolated storms near I80 in NJ through LI and southward. Saturday: May be dry, but modeling still showing small chance isolated shower. Sunday-Monday: Potential nw flow severe event? Still cant get rid of this yet. Modeling has this I90 northward. IF it doesn't occur, then likely renewed heat wave where it doesn't end this week per other posts here...Sunday-Tuesday or Wednesday. Might get to near 97 again in the city- but for now I'm just thinking the rest of this week and allow the models to develop better consensus on short waves-heat and convective thrusts from Sunday the 26th-Wednesday the 29th. 729A/22

Good Wednesday morning everyone, Add graphics etc as you like. After reevaluation using guidance through 09z/22, made no change regarding the topic discussion. I'll add two incomplete graphics for the overnight event which is ongoing (eastward and soon ending) the extreme east portion of our NYC forum (LI,CT). Lightning accumulation graphic was snapped around 514A, and the Radar storm total will continue adding on for LI/CT through 830AM. Today: Modeling is trying to focus a line through virtually all of our area 5-9P, but there could be isolated storms ahead of it this afternoon, and maybe another cluster or two trailing behind the primary line - up till about midnight, especially se NYS and nw NJ. Thursday: wind fields look a little stronger to me for an even better chance of SVR/FF late in the day or evening. Monitor SPC guidance for any upgrade in their thinking. FOG may be a problem the next two afternoons along the south coast of LI, especially Suffolk County. Otherwise heat wave should continue non marine influenced coastal plain next two days. Had .07 on the northern fringe of the southern overnight complex (~1235A). Saw one quarter inch near Patterson, NJ. 614A/22

Fortunately the EC is not known for its convective prowess. However, am a little concerned that Thursday especially may not produce much if the wind at 850 shifts to west or northwest too soon on Thursday. Need to reevaluate Wednesday morning. One day at a time.

Biggest convection both Wednesday and Thursday should be afternoon or evening, depending on where you are. And so... probably okay for a 90 min drive Thursday, but subject to an update Wednesday or even Thursday before 6A. Not sure if anyone noticed, but SPC 13z D1 marginal update has been bulged northward slightly in PA. Thinking that might reflect fairly robust nighttime WAA out there. We'll see how it goes.

After yesterdays long range failure of convection (arrived Sunday night), must look ahead. Modeling, SPC, WPC graphics all suggest opportunity for heavy convection Wednesday-Thursday (22-23). Attached the 6 hr County Average threshold FFG, with hourly guidance even lower amounts. This shows vulnerability in parts of ne NJ and se NYS, plus urban paved environments. SPC Days 1-3 is attached as issued early Tuesday. Also, added a brief 06z/21 GFS snapshot of modeled winds aloft for LGA via Bob Hart's web page (time is in UTC). Note the near 30 kt or greater westerly flow at 500 and 300 MB, showing the idea of enough wind to foster development of SVR organization and strong downdrafts. In these two days, "isolated" storm totals of 4" easily possible with 'general' two-day total amounts of 1/2-2". Warm Air Advection (WAA) instability burst (KI popping into the upper 30s from southwest to northeast by daybreak Wednesday driven by a modeled small 850MB 30 kt jet core in central PA overnight) 'should' develop some briefly heavy showers or a thunderstorm for parts of our NYC forum early Wednesday morning, especially nw NJ/se NYS. After any clusters pass, cloud debris/instability pooling and surface wind shift convergence boundaries will probably be the determinants of when and where heavy convection occurs Wednesday afternoon through Thursday evening. Heaviest should be afternoon-early evening and per modeling, think the bulk of the FF/SVR should be along and north of I80 (far northern NJ, se NYS, CT and LI) but I defer to your assessments, and those of the NWS offices/SPC/WPC, and the modeling from the HRRR and SPC HREF. 734A/21

The future from my perspective: will begin a new two day topic for Wednesday-Thursday and add a couple of graphics by 740A. Next heat-convective event sometime between Sunday afternoon and the middle of next week, but modeling is variable as to which day? and modeling is also variable if indeed another heat wave occurs for NYC between the 26th-29th. I do note the GFS operational has reverted to a potential nw flow event here Sunday (00z/06z 21 cycles), but other global models differ (early or middle of next week). No matter, opportunity for action continues in the overall pattern sometime between Sunday the 26th and Wednesday the 29th.

Looking back the past two days... looks like 97 was the good non-marine influenced max T for the 19th-20th. Even though the HI made it up to near 103-104 in Toms River and possibly parts of LI, overall, I think the max HI was closer to ~100 .. and so from my perspective yesterday-Monday the 20th, did not quite live up to the intense heat that was suggested in some of the modeling (trough too close and so some afternoon lowering of the TD near the city on a westerly surface wind).

Wrapping up: nothing happened Monday afternoon, probably due to some drying aloft, trough too close (West-northwest wind too close to the city).This gives the dry short term modeling the correct answer, (long term modeling was too robust for Monday the 20th).

Nothing going on and probably little or none today in our area. Closest shower at 335P looks near DCA. Where there are cu fields, they still look pretty flat. Was thinking LI breezes could go but apparently too stable, so far. 338P/20

Wantage NJ .02 in a brief heavy shower around 215A. 75/74 as of 638A..small patches of blue sky seen through deck of AC. Updating the outlook from previous mornings. Wednesday: Please see SPC D3 marginal risk for our area. Wind fields stronger than those of late yesterday and today, and much more CAPE/KI will be place. Thursday: Convection still possible. Sat night-Sunday strong thunderstorm northwest flow event...may be delayed to Sun night-Monday? Looks potent for a quick moving complex somewhere through the northeast quad of the country. Monday-Wednesday: EC is bonkers on heat and usually overdone - subject to large error...but ring of fire convection possible (around the rim of the Great Lakes northward bulging ridge) -in other words, 1 or 2 northwest flow events possible if not mid level thermally capped. Uncertain but interesting. 648A/20

Good Monday morning everyone, Have attached what happened since 6PM yesterday, lightning, severe reports and radar for our area (most of it after 22z/19 though there were a few isolated cells early Sunday afternoon in se NYS/ne PA). The reason for the attachments... the overnight reality was not well modeled by the models including the HRRR and SPC HREF (and still not as of 6AM/20). Which leads me to this afternoon. Please see SPCD1 and local NWS offices for details on any evolution. I know most of the models are dry except UK/Canadian have spotty action but I'm not convinced. I suppose most of NYC forum is out of the convection this afternoon, but I'm still alert for isolated eastward moving severe storms in our area developing 2-4PM this afternoon I95 corridor eastward, inclusive of extreme southern CT, LI, eastern and southern NJ. Plenty of instability with a surface trough nearby. Wind direction will start sorting itself out with mixing around 9 or 10AM and then we'll see what we have. If no new CU fields ~11A, then probably nothing. Mid level lapse rates increase this afternoon-especially south of the modeled 500MB -5C cap aligned just nw of I95 at 18z (thats why I chose I95 corridor southeastward and also thinking back to yesterdays SPC D2). GFS CAPE looks more reasonable then that very low 18z CAPE of the EC. 637A/20

Modeling looks terribly slow and ineffective for two bands of convection this evening in NYS/PA. Running much faster. If this is true... parts of our NYC forum, at least se NYS and nw NJ are going to experience a brief heavy shower or gusty thunderstorm between 815PM and midnight and possibly again near 2AM Monday. That leaves us with what for Monday afternoon? I think a pretty ripe environment for big storms maybe even up just N of I80...with interestingly large mid level lapse rates, especially I78 south. Not promising big stuff near NYC but it seems to me modeling (not SPC - check their Marginal D2) is missing potential svr/ff, especially southern part of our forum Monday afternoon 2P-7P. Will rereview how things are going Monday morning around 7A, but for now... it looks like big heat has generated big storms Sunday evening just west of the forum and I think very poorly modeled. If someone has seen a model that is performing admirably in PA/NYS to the Poconos and Catskills, please let us know. 735P/19

Posting topic shortly... too much going wrong with modeling. Not sure how this ends up. Topic will describe uncertainty. May be useless but you have to be bothered by terrible modeling. Walt 722P Results and update posted at 637A/20.

Wantage (southern part). Max 91.4. Currently 91/73 at 5PM. on SVR for Monday... think SPC did right cutting back on nw extent in our area. No topic at this time. Think it could go big near I80 south between 2-5P and then out of NYC forum by 8P. might start up here in nw NJ/se NYS as isolated thundershowers and grow in the more favorable environment I80 south some time around 2 or 3P. Meanwhile, leftover severe remnants from the POH Valley NYS/PA seem destined to die se NYS/extreme nw NJ as showers/iso thunderbetween 2A-5A Monday. Will comment in the morning based on SPCD1 etc. Enjoy the heat and cooling breezes! 503P/19

Good Sunday morning American Weather participants! Rutgers site looks to be working as of a few minutes ago. If not, please inform. I'd send them a message but I think whatever it was to halt posting data, is resolved. High T yesterday here in Wantage (less than 1.5 mi from Space Farms) was 89.6-- so that goes as 90 and our heat wave has started. Temp Outlook: I've no change in overall max T/HI through next Sunday26th as per yesterday. GFS continues to try to cool us Fri-weekend while EC/GGEM do not-jury still out but am not buying all that relief in the GFS around here. GFS may be too robust with a short wave passage late this workweek and the subsequent associated pattern cooling. The EC ensemble 500MB pattern is decidedly weaker with that far eastern Canada cooling. Convection Outlook: Monday..a little worried that upstream severe this evening sends dying showers/thunder in here predawn Monday, with the associated surface wind shift too close for us in the afternoon except southeastern New England and s of I80 in NJ. That could mean nada for most of the NYC forum except NJ s of I80? However, it's too early for me to throw in the towel. While modeled CAPE is not quite as robust on the EC (my main cue guide as prior operational modeling), it still has plenty of PWAT and KI over us through early Monday afternoon. Won't start a topic on the SPCD2 marginal(I liked it's read) until late today. Want to see the HRRR (12z version through 18z Sunday pick up on something around 17z, and certainly the 18z run pick up on something for Monday afternoon). UK has a little something tomorrow morning while other Global models in general have dried out the QPF here in the NYC forum coverage area. So, the heat may be wasted for convection here...I just don't know, but the past 24 hours of modeling has me much less certain on Monday's convective threat outcome. IF convection does flare, mid level lapse rates look pretty sizable to enhance convection. Winds marginal. Just too early. Wednesday should have some pretty good activity in our area...stronger signal than tomorrow=Monday. Thursday...? potential exists for sizable convection but need to focus on Monday, Wednesday first. Saturday night-Sunday: GFS is basically zip but I like the GGEM-EC staying on message with main uncertainty where the strongest convection will track. A northwest flow severe signal is d present (mid level northwesterly enhanced flow) with capping a possible issue (along the edge of the -4C 500MB might be where to find the convection). So this too is uncertain, because of modeling differences. Til later--- I'm probably off line til late day. 838A/19

Wantage 84/65 few this sc generated since Noon. Basically brilliant sunshine. Maybe we'll have a clear shot at the Comet this eve before a little AC forms later at night.

I'd heard of that near LA and absolutely-common sense! Have no idea of NWS plans. I think the military has been using WBGT as their guide for 50+ years. Posted this article because of the Law relating to HI litigation. This may accelerate research-and any subsequent change and comments. I've drifted away from descriptive adjectives spicing up the weather and just letting the numbers dictate local action.

Noting no convection for NY forum Monday in the 12z/18 NAM. Might be because surfaceT forecast in the NAM3k is about 5 degrees too low for the afternoon. I think the convective temp is modeled around 95. So we're going to need to get to that value to get convection started. Could see this as a bit later start Monday... maybe closer to 3 or 4P if it takes longer to reach 95?? Still uncertainty.