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Everything posted by Rainshadow

  1. 00z Jan 19th GEFS Above normal 500mb heights return on the 22nd thru the 24th preceding the next system. On the 25th when below normal heights return (been consistent for a week). We still have an Aleutian trof, eastern Pacific ridging, eastern NOAM troffing, -NAO and Hudson Bay TPV outlooked. Angle of the coldest looks west of us. This is pretty much the same story through its run (NAO may become more negative, well anyway outlooked). But starting about February 1st, the Pacific flow looks more zonal even with our heights still below normal. the above normal SE heights are gone. Our heights return to near normal at the very end on February 3rd. If the GEFS bias is consistent, this is probably a week too fast at flattening the Pacific. We will follow the can. NAEFS for the week of 1/27-2/3 is finally confident of below normal temps here. 00z Jan 21st GEFS Above normal heights return on the 22nd thru the 24th preceding the next system. On the 25th when below normal heights return. Can see the double barrel energy in the troffing and the early next week system with a neg tilt look to it. On the 28th the NAO (as an index) looks positive, there is an Eastern Pacific Ridge and the PV in Hudson Bay not as great looking as earlier. Rest of January pattern is retrogressing (ridging thru Alaska on the 31st) as above normal heights return to our area. Angle of cold outlooked farther west. This is faster than two days ago. As February starts, the flow over the Pacific becomes more zonal, tight atypical nino pattern with below normal heights in Canada and above normal heights southern conus. 3rd thru the 5th our heights are near normal. South of Alaska troffing is outlooked at end of the run. NAEFS for the week of 1/29-2/5 is confident of below normal temps starting just north & west of the Philly metro area westward thru the Northern Plains. 00z Jan 23rd GEFS Current above normal 500mb heights are replaced by below normal heights on the 25th. This persists thru the 30th, although the > of the cold gets farther west as a northwest Atlantic ridge tries to retrograde west. Above normal heights eke to the west into our area as February starts. This is a day later than two days ago. On February 1st, we see a closed ridge over the Bering Sea; a zonal looking ridge/trof/ridge pattern across the conus. The EPO looks weakly positive, the nao is negative and a weaker TPV over northern Hudson Bay. Our 500mb heights are near normal until the 4th (below) by product of a cold shot. The Pacific does not look cold with ridging in the Aleutians and troffing across the eastern Pacific. Above normal heights (yeah la la la la la land) envelope most of NOAM at the end of the run on the 6th and 7th. Personally though I can see this happening as a reboot or change given this is about the 3 week mark of the SSW vs what the GEFS was previously pushing about this occurring a week earlier. Granted by then the MJO could be in colder phases and thus negate it altogether. NAEFS for the week of 1/31-2/7 is slight confident of below normal temps in our area, guessing cold weighted to the start of the week now that the GEFS has chilled. 00z Jan 26th GEFS Current below normal 500mb heights pretty much persist through February 2nd. The TPV passing to our north re-inforces this. Above normal heights arrive from the west on February 3rd. It is a net loss of two days from the previous post (three days). Dollar cost averaging or not, this is a pretty zonal looking flow as of February 3rd with the epo weakly negative (no ridge thru Alaska), +nao, -pna and TPV retraction to Baffin island. Above normal heights persist into February 9th until the TPV starts sinking to Hudson Bay again. The EPS & GEPS do not look like non stop warmth from February 4th thru the 10th, but they do show an overall warmer pattern relaxation. NAEFS for the week of 2/3-2/10 is confident of near normal temps in our area. Given the way this has worked this winter, i'd say that 8 day period would average above if the ensembles are semi-close. MJO is currently in Phase 5 (from Mike's site), new outlook is for a more stout MJO for the umpteenth time this winter. Using a two week lag rule, this would support that relaxation depicted and a MJO related return to colder weather thereafter.
  2. I may end up being dead as a door nail wrong about this, but the GFS clean solutions just reek of its bias of plow driving cold air to Panama City. Granted it has a whole lot more with the first and nothing with the second like other models, but my thoughts would be a non-GFS solution comes to fruition for the first half of next week. Confidence in the GFS/GEFS is not aided by the fact it has even been awful within 84hrs with snow this month, not that any model has been grabbing the brass ring. It still doesn't necessarily mean a 2" or greater snow as it would depend on a near perfect track and climo is working hard against us. But for places north and west where it can snow this time of year and are allegedly in the clear for now, their window is open a crack.
  3. The current thread is over 50 pages and don't want to split early next week out. Please put any threats starting in February in this thread. Thank-you!
  4. Speaking of next week as far as teleconnections go, there has been a "negative GEFS bias" with all of them, especially at longer ranges:
  5. 00z March 11th GEFS Strongly above normal 500mb heights peak March 12th-16th. Below normal 500mb heights try try try to get into the area on the 17th, but struggle to cover the entire area until the 20th. BIAS corrected GEFS PNA index peaks on the 18th, but remains somewhat positive thrut as does a +NAO. EPO returns to a more neutral index look, but I would say looks more positive than negative on the forecast maps. Below normal heights exit on the 23rd (same as two days ago) as flattening of PNA ridge continues. A tendency toward above normal heights concludes this run on the 25th & 26th as does a (ha) hint of a -NAO east. NAEFS for the week of 3/19-3/26 has our area in high confidence of near normal temperatures. This means either the 17th and/or 18th should be cold, or it was just a warmish modeling jump for a day (it looks like that). Either way the 500mb tendency looks like a cold start/warmer finish. MJO is in Phase 4. Tossing the retrograding WH outlooks and assuming a phase 5 is coming, this corroborates the PNA ridge for next week. Phases 6 & 7 are warmer. So either entering the COD (doubt it very much) or exiting phase 5 support the end of the current GEFS/GEPS/EPS, slightly higher confidence than average for that forecast time range. Warm week/cold week/warm week if all goes accoring to plan. 00z March 14th GEFS Strongly above normal 500mb heights go bye bye on the 16th and get replaced by below normal until the 20th. Same as three days ago. Still positive PNA with an anomalous trof over the SERN Conus and outlooked offshore cyclogenesis as spring arrives. As PNA is outlook to flatten, above normal heights return on the 23rd. (+EPO/+NAO). This overall pattern holds to the end of its run through the 29th. There is either west coast or eastern pacific troffing and any hint of -NAO is -NAO east. NAEFS for the week of 3/22-3/29 has confidence of above normal temperatures in our area. This rolled over yesterday after losing cold I am guessing from the 20th & 21st. MJO is in Phase 5 (or 4?). It still looks pretty active and outlooks still have it going into the COD. But at least now they have it progressing vs the silly loop de loops into phase 3 they once had. Mike's site outlopok for the last week of March are warm MJO phases for our area for March. So call me confident about a warmer than average send off to this Smarch. 00z March 18th GEFS Positive PNA below normal 500mb heights last til the 20th and then come back with offshore/east development on the 21st thru 23rd. As the +PNA ridging moves eastward across NOAM, above normal heights return on the 24th (one day later than the outlook from four days ago). A negative NAO is outlooked to develop and heights return to near normal on the 26th. the long run of above normal heights gone. On the 26th there is the -NAO E and neutral looking PNA (maybe index positive) with trofs across the southwest & southeast CONUS. Latter with latest day 9 Euro snow. As that SE trof exits, above normal heights briefly return on the 29th & 30th, +NAO at that point. Til the end of its run on April 2nd, we drift in/out of normal and slightly below normal heights with mainly a zonal flow. NAEFS for the week of 3/26-4/2 has pretty high confidence of above normal temperatures. So much for the GEFS thoughts. EPS does not look that cold either. MJO is in Phase 5. COD location I am guessing because of 200mb winds, but convection still looks rather robust and that is what drives the latent heat release. So warmer phases on the way until maybe a real COD after phase 6 or 7. A warmer than average send off to Smarch still looks there. 00z March 20th GEFS Brief above normal 500mb heights until neg tilt trof (below) on the 21st. As the +PNA ridging moves eastward across NOAM, above normal heights return on the 24th (same as two days ago). A negative NAO E develops and heights return to near normal sooner on the 25th. Rockies PNA ridging/ -NAO E bring below normal heights to our period of interest late on the 25th. Breakdown of the -NAO E/ PNA ridge brings above normal heights back on the 28th. This persists to the end of March. As Sapril starts a series of Pacific trofs bring an el nino look with below normal heights across the southern & southwestern conus. Our heights return to above normal on April 3rd & 4th (end of run). NAEFS for the week of 3/28-4/4 is weakly confidence of above normal temperatures. MJO as far as convection goes is in Phase 5 almost phase 6. The amount of convection and the 850mb & esp 200mb push into the COD. The models were right (I was wrong) about it weakening. Although convection is not nil and any convective forcing would assist in warmer phase solutions going forward. I like the split of different MJO factors as convection still drives the ridging bus. Granted if there is not support aloft, it won't be easy going forward.
  6. Rainshadow

    FV3 Future GFS Implementation Date Postponed UFN.

    I was thinking bigly, but I will settle for Panama City for now.
  7. A couple of comparison maps from night run. If anyone has other links or info, please post.
  8. Rainshadow

    FV3 Future GFS Implementation Date Postponed UFN.

    Such disappointing night runs, I was expecting snow to Panama by now.
  9. Day 7 UKMET (thermals unknown):
  10. Well 12 hours later and different solutions. The OP GFS & I Won't Believe It Til It Comes On Board FV3 have any snow chances with the initial cold frontal passage and wave Monday night. The Euro, CMC, ICON & UKMET say what cold frontal passage precip? The OP GFS & I Wont Believe It Til It Comes On Board FV3 then build a high pressure system over the area on Tue & Wed & say enjoy the crisp clear weather. The ICON & UKMET say ok, maybe no precip, but it is close. The Euro says enjoy your waves of pcpn and two shots of snow (one early Tuesday & one early Wednesday): 1.5" total. The CMC brings the wave so far north it is too warm for snow. As much as the GFS & EC are not on the same page, their ensemble means percentage wise are close. The EPS has 25 (out of 51) members having it snow in PHL, 12 with 2" or more & 4 with 6" or more. The GEFS has about 15 (out of 21) members with snow (Monday evening helps), 5 members with 2" or more & 2 members with 6" or more. The EPS clustering is harder to determine with this one, but the ones that have it snowing here have a more strung out, southern track and non OP CMC solutions which was rain. There is a clustering like the OP GFS that has nothing, but that number appears to be lower. So with the EPS it is a track issue, stronger, closer to us low forgetaboutit; more strung out, secondary forming, farther south low where we are closer to the northern fringe of pcpn that is the snow. EPS mean 1.6". CPC 6 to 10 day too far along today unless this pushes back beyond Tuesday Night/Wednesday with 12z run. I suspect if that happens we go rain anyway.
  11. Rainshadow

    Temps/Obs/Boring Weather Discussion

    We hit the 50 page threshold, so with the start of the new season, we will start a new thread. The 69F at Midnight cost PHL the chance to tie 1978 for the most number of days with mins of 70F or higher for August.
  12. There appears to be three clusterings with the 12z EPS. First with Monday night's underrunning, just looking at Philly only 6 of 51 members have it snowing. There are a few hot (>6") members for the northern Poconos. Then for Tuesday/Wednesday, 17 EPS members have it snowing in Philly, 11 of them have 2" or more and 3 have 6" or more. Like the 00z run, one of the >6" is a Tuesday + Wednesday event, only one that has that. Otherwise, the two day, two hit idea has gone to more of one and done on the 27th. There is a large clustering that is like the OP, suppressed and then too late or east. There is another clustering like the UKMET, a wave into the Ohio Valley and then some redevelopment, the wave development is stronger and snow occurs. There is a smaller clustering kind of like the OP ICON where the wave/low gets so far north in the Ohio Valley, it is rain.
  13. Hello, with this weekend system Tom & I will start the new cold season qpf verification. Like last season, we will wait until there is a clear end within 84 hours (to include the nam & sref) before starting any evaluations. Last season it was all about the EPS: out of 48 events, it came in first place 20 times. While the GEFS gave it a run for its money, the NAM came in last place in 16 events. If all models had equal skill, they would have come in first/last place 8 times each. This is the average error & bias (in inches) for all events: This was the accumulative stats for predicted/observed snow events at PHL:
  14. The EPS members (PHL ensemble mean about 1.5") that have snow (or non-rain) here look similar to the current UKMET solutrion, of a more significant wave on the front and not as suppressed as the OP EC.
  15. Rainshadow

    Winter 2018/2019 vent/meltdown thread

    I have golfed less this winter than any winter since I retired and this winter looks to rank as the 2nd least snowiest here since I retired. The ultimate kick in the junk was the week of February 4th, high temps in the 50s & 60s and golf courses still frozen and basically unplayable (although I was out there hitting "shots" out of semi-standing water) in spite of the air temperatures.
  16. CPC 6-10 day outlook switched to cold for us. There was one analog that had snow for Philly. Looks like the Monday night scenario of a cold frontal passage and then some wave or true low on the front to enhance precipitation. The number one analog was all rain. Another analog had mixed precipitation a few days before, but that is a stretch to go that far friom the centering day. Unless this somehow gets centered on Thursday tomorrow, we are going beyond the analogs. The EPS solution are all over the place, which is a blessing vs just kissing the operational's or control's arse showing there is (you don't say) alot of uncertainty about next week. These are both for PHL: (I dont know why the different sizes, but the #1 analog was centered on 3/20/1998.
  17. Rainshadow

    Winter 2018/2019 vent/meltdown thread

    D+ Final grade. If it somehow manages to snow or sleet next week, I might lower the grade to a straight D. No credit for driving in a run when you are losing 20-1.
  18. Rainshadow

    FV3 Future GFS Implementation Date Postponed UFN.

    Wrong version and run, but we are getting there!
  19. The 12z run was only apropos for those standings and the way this winter has gone. Tuesday into Wednesday "went south" collectively with now the greatest snow (or non liquid) chances with the initial underrunning shot on Monday night. The OP EC did have this on the overnight run too, not as snowy (although I suspect some of this is sleet) as the day run. This might have been the first hit of some of the Euro ensemble members overnight that had double hits. Anyway I would surmise (thank-you Captain Obvious) north better than south with this one. The second one, by the time the Euro brings it here, we have lost the cold air. Of course all of this will change in 12 hours.
  20. I have to walk back previous post about the GEFS. It managed to avoid a last place finish with yesterday's non event as it had some rain mixed in and knocked down the "snowfall" end of it, barely making it into 5th place in front of the OP GFS. At anyrate this cold season has proven that no model has had a monopoly on snowfall/track forecasting skill. I would say the UKMET has averaged better than the rest but it reminds me of the 2010 NFC West: (The SREF does have the advantage of not having to forecast beyond 84 hours).
  21. We can start the Thursday event with the 00z run this morning. (19th). End it at 12z on the 22nd. I know GFS has some secondary pcpn later on Friday, but this looks like a separate system and for now it is less than one tenth.
  22. Yes the EC won, it is great at forecasting nothing & being right. The GEFS ended in last with qpf, but ended avoiding the cellar for the first time this month to the OP GFS as some of its members had some rain at PHL, so in spite of higher qpf, its snowfall predictions averaged just lower than the OP GFS. NEW2018-9qpf.xlsx
  23. Rainshadow

    FV3 Future GFS Implementation Date Postponed UFN.

    18z run today.