bluewave

The 18z RGEM came west with the cyclonic loop closer to the 18z HRRR.

60-70 mph near MTP and 80 mph near MVY. We will really have to watch where that cyclonic loop occurs for the winds. Those storms that back in from the east are notorious for wind damage near the center.

While these long range SPV forecasts can be very speculative, the latest extended EPS doesn’t have the stronger rebound it did last week. It would be good news if that second dip near the start of December idea has merit. But these forecasts beyond 15 days can often be very uncertain. New run Old run

If you ignore the 0z run, the 12z Euro is similar to 12z yesterday. Still very heavy rains area wide and possible gusts near 70mph on Eastern Long Island. The problem with winter storm tracks was suppression even a day before the storms. So we will be ahead of the game if the suppression issue is fixed. This old bias led to snowfall shifted too far south like during the January 2016 blizzard. 12z today 12z yesterday

High of 77° so far at Newark and only 55° north of the warm front at BDL.

The HREF says make sure that leaves aren’t blocking your storm drains.

The 3km Nam has 70 mph gusts close to Eastern Long Island. But the exact location of where the cyclonic loop occurs will be important. Models may be struggling on where to place the subtropical system with the multiple weaker lows to the west.

New all-time 24 hr rainfall records around Sacramento and wettest October day in San Francisco.

That has been the story since the super El Niño. Warmer winters overall with a strong WAR or SE Ridge in the means. But impressive blocking intervals that always seemed to produce snowstorms for us. So more of a snowy and mild spring in the Rockies type of winter pattern. The record SSTs to the east were like rocket fuel for heavy snowstorms.

The 18z extended HRRR looks more like some of the EPS members.

Looks like the major upgrade also improved the EPS. https://www.ecmwf.int/file/299239/download?token=QzX-fS7a On 12 October, ECMWF implemented the second upgrade of its Integrated Forecasting System (IFS) in 2021. IFS Cycle 47r3 includes numerous changes to the forecast model, observation usage and data assimilation system, with contributions from many teams across the Centre. There are major developments to the representation of moist physics in the model and increased observation usage in cloudy regions in the assimilation. The upgrade improves the large- scale atmospheric circulation and reduces tropical cyclone track errors in both high-resolution (HRES) and ensemble (ENS) forecasts. Several forecast products are modified, such as visibility and wind gusts, and new products are introduced, including clear-air turbulence. Cycle 47r3 brings a major revision to the representation of moist physics in the IFS as well as improvements in the assimilation of observations and increased usage of satellite data in cloudy regions through the extension of the ‘all sky’ approach. An important impact on the forecast is the improvement of the atmospheric circulation, as seen in the increase in skill of extratropical geopotential heights and winds, and with a reduction in wind errors in the tropics of several per cent. The ensemble-mean of error in tropical cyclone position is reduced by 10% between forecast days 2 and 5. There are changes to the character of precipitation, with improvements in the precipitation PDF and in strongly forced convective systems. As well as the many positive signals, a significant change in the physics inevitably leads to some deteriorations, for example in total cloud cover, and these will be addressed in future IFS cycles. There are several new forecast products, such as clear-air turbulence, and improvements to existing products, including visibility and wind gusts. Overall, the package of changes in Cycle 47r3 is an important step in the development of the IFS, improving performance overall, extending our use of existing observations and providing a stronger foundation for further development of the model and data assimilation at current and higher resolutions.

New lowest pressure record for the area off the Pacific Northwest coast.

If the Euro performs reasonably well with this, then maybe the big moist physics upgrade will turn out to be a success. The hope is that the coastal storm track suppression issue with our snowstorms will be fixed. It would be nice seeing the Euro amped up with snowstorms like the NAM was with the January 16 blizzard. The 12 EPS is more tucked in than the OP

Impressive subtropical structure on the 12z Euro. Convection wraps almost completely around the center. An eye-like feature briefly develops.

Looks like too much onshore flow on Monday at JFK. But areas away from the ocean influence have a shot at 80°. It’s tough to use analogs before 2010 since our climate has changed so much since then.

Yeah, those record SSTs are rocket fuel for storms. https://mco.umaine.edu/gom_sst/

Monday looks like our last day of potential record warmth in a while. Newark may make another run 80° with a record high of 79°.The first two months of fall have followed the delayed fall theme of recent years. We are the warmest on record through the 23rd at several locations. Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Rank Ending Date Mean Avg Temperature Sep 1 to Oct 23 Missing Count 1 2021-10-23 69.7 0 2 2017-10-23 68.6 0 - 2007-10-23 68.6 0 3 1961-10-23 68.4 0 4 2005-10-23 68.1 0 5 1990-10-23 67.7 0 6 1971-10-23 67.6 0 7 1959-10-23 67.4 0 8 2016-10-23 67.3 0 9 1968-10-23 67.2 0 10 2011-10-23 67.0 0 Time Series Summary for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Mean Avg Temperature Sep 1 to Oct 23 Missing Count 1 2021-10-23 68.1 0 - 2017-10-23 68.1 0 2 1971-10-23 68.0 0 3 2007-10-23 67.6 0 4 1961-10-23 67.5 0 5 2005-10-23 67.2 0 - 1959-10-23 67.2 0 6 2016-10-23 66.8 0 - 2015-10-23 66.8 0 7 1983-10-23 66.7 0 8 2018-10-23 66.4 0 9 2011-10-23 66.2 0 10 1995-10-23 66.1 0 - 1990-10-23 66.1 0 Time Series Summary for ISLIP-LI MACARTHUR AP, NY Click column heading to sort ascending, click again to sort descending. Rank Ending Date Mean Avg Temperature Sep 1 to Oct 23 Missing Count 1 2021-10-23 66.7 0 2 2017-10-23 66.5 0 3 2005-10-23 65.9 0 4 2007-10-23 65.7 0 5 1990-10-23 65.5 0 6 2018-10-23 65.2 0 - 2011-10-23 65.2 0 7 2016-10-23 64.9 0 - 1980-10-23 64.9 0 8 2015-10-23 64.4 0 9 1971-10-23 64.2 0 10 2014-10-23 63.6 0 - 1998-10-23 63.6 0 - 1983-10-23 63.6 0

Looks like an impressive hybrid-type development.

Unusual storm evolution on the 12z Euro. Cutoff low taps deep tropical moisture from offshore hybrid type low. The moisture channel along an inverted trough-stalled front becomes the focus for very heavy rainfall. Almost looks like a PRE merging with the cutoff.

The impressive part is that we got one of the stratospheric warming precursor patterns this month. The strong +EPO -NAO matches one of the clusters in the paper below. While the models do show a quick recovery of the vortex, this type of pattern would be a window of opportunity during DJF for snow. https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2017GL074611

The upcoming forecast is a great example of how an early season stratospheric warming can push back against an unfavorable Pacific. The EPS now has a stronger +PNA -NAO pattern to start November. The series of impressive storms in the Northeast this week will finally flatten out the SE Ridge. So Monday looks like it will be the warmest day for a while. Even though we will experience more troughing going forward, the airmass under the +PNA -NAO block is initially of Pacific origin. So much less warm than the 70s and recent 80s. But nothing overly cold yet for this time of year. This type of push back interval against the Pacific is what we will want to see in DJF for our snowfall windows of opportunities. New run Old Run

We almost always get significant storms with such a strong -NAO pattern. But it took a while this month since the -NAO linked up with the SE Ridge and lead to record warmth and storm suppression. Now the record Pacific Jet is able to undercut the ridge. So we are getting two big cutoff storms next week.

Remember when the models had Monday as cool and wet? Now we get warm sectored. The usual warm spots in NJ may make another run on 80° with enough sun. New run Old run

Warmest fall on record through October 20th for many stations across the region.

Yeah, the warmer departures to the north pattern has been stuck in place since last winter.