wdrag

Bluewave post from 5-6 days in the morning on EPS pattern and beautiful weather was right. EPS again, I'm afraid. Erin or Fernand looks next up... from the guidance I see a recurve but maybe close enough to help reduce our Aug rainfall deficit.

Modeling issues: Sort of a bust for our no rain last night... ONLY the EPS got it right 24 hours in advance (00z/6 cycle). In the longer range it looked bigger up through NJ/PA (my post on OH Valley low aloft) but GEFS was dry and so many forecasters opted for 20% or less chance yesterday, instead placing the 20% for today. Then as we drew closer to yesterday, all the modeling tended to shrink southward and I gave in to the dry GEFS (my mistake), but alas the EPS still held onto a little, which is what we got up through about 40-41N latitude. See attached graphic. Ohio Valley had isolated 4-5" in w Central Indiana/e Central IL, with some 2"s just e of Cincinnati on the 4th-5th respectively. Then last night we got our minor amounts, mostly evening on previously dismissed chances. I would say pretty deficient modeling for the northern fringe of the ne moving rain areas. CoCoRaHs attached for yesterday here and IN/IL for the 4th.

Showers developing?

Sea breeze boundary w LI. Showers now at 250 pm

I was wrong relying on EPS for the OH Valley potential rainfall here. GEFS looks far superior for late this week, well in advance. My wrong. Now I worry about flash drought here in the Tri state, especially if we dont get late day convection. Wind ix not large but long days, high evapotranspiration and no rain are a concern imo, for. drought ion we cant get some decent rainfall in the next week or two.

LOTS of easterly flow in that EPS image... moisture.

Verification comments added to the initial post for July... actually imo, decently outlooked.

00z/3 GEFS and consequently WPC looks misleading dry and underplayed middle and end of this coming week... PA/NJ/NYS. Developing Ohio Valley upper low spells trouble this first week of August... before a major warming occurs 2nd and 3rd weeks of August-back to H&H then. So, I'll have to self criticize if the 00z/3 DRY WPC 7 day in PA/NNJ/NYS verifies-accountability for words Expressed. The rain may no exceed 1/4''' but I think something is coming to NJ/e PA/s NYS. Exactly how and when is my greater uncertainty. Difficult to get 7-8 consecutive days of no measurable. Can happen--- Adding verification to July in a couple minutes.

I am interested in the middle of next week. Ensembles say pay attention to what is going on in the Ohio Valley. Outlooking low prob flood potential here in our area later next week. See graphic.

CoCoRaHs reports... you see the 4"s and 5"s as a sampler. When you compare the max rainfly axis... I think the EPS had the best idea from the start and all ensembles had the max GENERAL 2-3" rainfall northwest edge of our NYC forum. HOWEVER: the value of the MAX potential SPC HREF rainfall posted on p1, was possible in our area. I've not seen max rainfalls but suspect iso 6". Therefore the thread had added value using the SPC HREF MAX rainfall...its never perfect but having the max occur in the center of the NYC subforum is no surprise... at least we were bordered N and S edges by the modeling and knowing it's imperfect permits leeway considerations. I always keep in mind lack of modeling perfection and leave options open. Click graphics for clarity. I chopped off the time covered but trust it's 7/30-31.

will post a CoCoRaHs 2 day total at 9A and add some positive comment about the ensembles (global, mesoscale),

This is accurate. for the locations posted---climate sites. Zooming in gets a few more stations but its only rolling 24 hour rainfall, deepening on the you select the map.

Heaviest rainfall in quick scan of weather underground data. Am sure more will come in soon... click of clarity. Ignore the 11.8. Not qc'd so amounts might be too high?\

Sampling of rainfall in narrow groups-swaths roughly 2PM yesterday- 8AM this morning. Click for clarity. Interesting 15 hours ahead. At 838AM added the NJ and NYS climate mesonet 24 hours amounts.

To get this started brief heavy showers have dropped at least 1 to 3 tenths of an inch in far nw NJ and se NYS since 2PM.

Follow NWS warnings-statements. A flood watch has just been issued by the NWS for a portion of the NYC subforum. I'd prepare for some delays Thursday-Thursday evening, possibly a few detours. If a road is flooded, don't cross it---turn around-done drown. Not worth the risk. We dont know where exactly 4+" of rain should occur but the potential exists as a slow moving frontal boundary possibly ends as a near northeast gale for LI. Plenty of PWAT (1.5"+) along with the RRQ of a strong confluence zone 5h-3H et across northern Maine-the Maritimes causes large scale overrunning of the southward sagging frontal boundary Thursday-Thursday night when the bulk of the heavy rain occurs. For now, it appears the region from I78 northward is vulnerable to excessive short fuse runoff but the HREF added graphic shows the isolated 7+ inches POTENTIAL(browns from the legend) just south and west of our NYC subforum. Nevertheless, this should be a somewhat interesting 48 hour period. For reference have added the 12z Wed 7/30 ensembles CMCE, EPS, GEFS as well as the 48 hour MEAN rainfall from the SPC HREF ending 12z Friday with magenta 1.5"+, and the MAX potential rainfall from the HREF which suggests isolated 7-possibly 10" but primarily southwest of the NYC subforum. See legend but dont take location verbatim and. dont necessarily believe 7+ can occur. Antecedent conditions are not excessively wet so large rivers are not likely to flood, but small streams, especially near urban areas could see overflow Flash Flood response.

Heavy showers organizing E PA. SPC HREF seems to have spot 7" MAX potential by Thu evening. Waiting completion of the HREF and then probably starting a thread for iso FF, detours, travel delays...sometime between 4-8P.

Will make my final decision on an OBS-Discussion thread for the upcoming rainfall which I think may produce small pockets of FF within the general 3/4-4"---iso max of 6" I think is possible. Primary event Noon Thu-Noon Fri (16z/31-16z/1), but preceded north of I80 by scattered heavy showers/iso severe 4PM-10P (20z/30 -02z/31) today. Most vulnerable via variability in the modeling - cant be sure where to lock it in but for our subforum between I84 and I95. Todays 12z SPC HREF will be my primary guidance, along with other supporting modeling --HRRR etc.

IF NWS issues a flood watch, will start a thread. Its marginal right now but I expect more or less what WPC has posted this morning with isolated max rainfall of 6". No thread at this time.

No thread from me on the around 100F (near record) heat vicinity NYC-EWR next two days---this July thread suffices. No thread from me on the 20z Wed-20z Friday probably 1-4" needed short term rainfall near and northwest of I95...isolated higher possible. Mainstem flood threat minimal. However several small area FFW possible Thursday CT/NYS/NNJ-LI, especially if SVR develops? If it looks worse tomorrow morning, will thread but for now relatively routine: fun for us but nothing extraordinary yet projected. SPC has marginal risk Wednesday and no SVR Thursday. That may need adjustment with time. WPC has a slight risk excessive Thursday and I like that---just not willing to overcommit a thread at this time. This based on on modeling seen through 00z/29 and WPC products available at 553A/29. Wish you a safe day.

Don's pre-summer outlook of a statistically significantly warmer than normal summer looks like it will come to pass with June-July at KEWR top 6. Very good statistical call barring a chilly August. Waiting on a thread til tomorrow morning for two 100F days at KEWR, (for me unexpected in lae June), to be followed by a potential widespread 1-4" forum rainfall with iso 8"... EPS through 12z/28 cycle continues strong on this, though edging northward. I also have to think there has to be a stripe of svr near the boundary Thursday? Just too early for me to be sure the EPS is going to be mostly correct. From what I can tell, WPC is so far, accepting the EPS solution.

CoCoRaHs rainfall for the Fri-Sun period. Much less than anticipated MAX rainfall. Click for clarity.

No thread from me on Tue-Fri til the last minute (Tue morning?). GFS MOS seems a little cool on the maxes Tue and Wed and too low on chance of rain Thu, maybe Fri too. GEFS coming up on qpf now... all ensembles under 2.5" but the EC OP Max #'s are interesting the past two cycles (isolated over 7" location-location?)

CoCoRaHs totals will be added sometime late this morning.

EPS 95-100 TUE and WED. central LI west. Also a 50-60% prob of 1+" in 24 hrs for NJ Thu into Fri. Not threading yet but may combine Tue-Fri morning for the two probable 100"s at KEWR Tue and Wed and a heavy rain event I95 corridor sewd later Wed-Fri... most ensembles not buying the cyclically repetitive EPS R+. Worthy of. monitoring.