GaWx

I’ve only rarely seen these very comfy conditions here this early in autumn, especially in recent decades: SKY/WX TMP DP RH WIND PRES REMARKS SAVANNAH ARPT MOSUNNY 75 53 46 N10 30.02F HUNTER AAF SUNNY 75 53 45 N5 29.98F

12Z Euro maps have a 500 mb temperature max of -5C near the center mainly on the eastside.

A beast:

What about airport service on Sun/Mon at the 3 major NYC area airports? How did past comparable storms affect service?

Thanks. 1. I understand and perhaps this will bust too cool. We’ll see. 2. Let’s see if today’s update is warmer. 2. You may have not seen my edit: “Keep in mind that this was based on yesterday’s 0Z Euro ens (the latest Euro Weeklies output available til after 4PM EDT today).”

John, Keep in mind that this was based on yesterday’s 0Z Euro ens (the latest Euro Weeklies output available til after 4PM EDT today), the 2nd shade of blue is -1 to -3C (so much of it for 9/28-10/3 could conceivably be closer to the -1C boundary), and this product uses a warmer climo base than most, the last 20 years: re-forecasts are derived by re-running an 11-member ensemble (1 control and 10 perturbed members) using the same calendar start date for each of the last 20 years. *Edited

It’s looking pretty chilly in the E 1/2 of the U.S. next week (this is for Sep 28th-Oct 4th): *Edited to correct date to Oct 4th

The MJO continues to avoid both the IO and the MC for a duration unlike any in recorded history:

The 0Z Euro ens increased the chance of “tropical cyclone activity” off the Mid-Atlantic coast during the weekend to its highest yet of any run and the highest possible, >90%! Yesterday it wasn’t as high for the weekend as it was peaking at ~80%.

0Z UKMET Nolo: still stays significantly S of Big Island but 9/30+ again turns NE to not too far S of Big Island: HURRICANE NOLO ANALYSED POSITION : 14.9N 156.1W ATCF IDENTIFIER : EP152026 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 25.09.2026 0 14.9N 156.1W 990 46 1200UTC 25.09.2026 12 15.6N 155.8W 985 57 0000UTC 26.09.2026 24 15.9N 155.0W 983 65 1200UTC 26.09.2026 36 15.9N 154.4W 985 55 0000UTC 27.09.2026 48 15.3N 154.7W 985 50 1200UTC 27.09.2026 60 14.2N 155.4W 988 42 0000UTC 28.09.2026 72 13.4N 156.4W 989 41 1200UTC 28.09.2026 84 13.5N 157.5W 988 43 0000UTC 29.09.2026 96 14.0N 158.6W 984 51 1200UTC 29.09.2026 108 14.7N 159.1W 982 56 0000UTC 30.09.2026 120 15.5N 158.6W 977 60 1200UTC 30.09.2026 132 16.1N 157.3W 975 61 0000UTC 01.10.2026 144 16.5N 155.8W 983 54 1200UTC 01.10.2026 156 17.0N 154.7W 989 52 0000UTC 02.10.2026 168 17.6N 154.3W 995 42

0Z UKMET: Fay still around at 168 moving NW: TROPICAL STORM FAY ANALYSED POSITION : 30.0N 41.9W ATCF IDENTIFIER : AL062026 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 0000UTC 25.09.2026 0 30.0N 41.9W 1014 26 1200UTC 25.09.2026 12 30.1N 42.8W 1014 31 0000UTC 26.09.2026 24 30.0N 43.8W 1014 30 1200UTC 26.09.2026 36 30.1N 44.6W 1014 27 0000UTC 27.09.2026 48 30.1N 44.8W 1015 23 1200UTC 27.09.2026 60 29.9N 44.9W 1015 23 0000UTC 28.09.2026 72 29.6N 44.9W 1016 22 1200UTC 28.09.2026 84 28.7N 45.3W 1015 22 0000UTC 29.09.2026 96 27.7N 46.1W 1014 22 1200UTC 29.09.2026 108 26.8N 47.2W 1012 24 0000UTC 30.09.2026 120 26.2N 48.5W 1012 26 1200UTC 30.09.2026 132 26.1N 50.1W 1011 26 0000UTC 01.10.2026 144 26.3N 51.5W 1012 29 1200UTC 01.10.2026 156 27.2N 52.3W 1011 30 0000UTC 02.10.2026 168 28.1N 52.9W 1010 32 ———— 12Z 9/25/26 UKMET run for Fay: TROPICAL STORM FAY ANALYSED POSITION : 30.1N 42.4W ATCF IDENTIFIER : AL062026 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 25.09.2026 0 30.1N 42.4W 1014 31 0000UTC 26.09.2026 12 30.0N 43.2W 1014 27 1200UTC 26.09.2026 24 30.1N 43.6W 1014 28 0000UTC 27.09.2026 36 30.1N 43.6W 1015 24 1200UTC 27.09.2026 48 29.8N 43.4W 1014 23 0000UTC 28.09.2026 60 29.0N 43.2W 1015 24 1200UTC 28.09.2026 72 27.7N 43.3W 1014 26 0000UTC 29.09.2026 84 26.3N 44.7W 1013 26 1200UTC 29.09.2026 96 25.3N 46.5W 1011 25 0000UTC 30.09.2026 108 24.7N 48.7W 1011 27 1200UTC 30.09.2026 120 24.7N 50.8W 1011 28 0000UTC 01.10.2026 132 24.8N 52.7W 1011 29 1200UTC 01.10.2026 144 25.3N 54.4W 1011 28 0000UTC 02.10.2026 156 25.6N 55.4W 1012 32 1200UTC 02.10.2026 168 25.7N 56.4W 1011 31

BULLETIN Tropical Storm Gonzalo Advisory Number 1 NWS National Hurricane Center Miami FL AL072026 200 AM CVT Fri Sep 25 2026 ...TROPICAL STORM GONZALO FORMS SOUTH-SOUTHEAST OF THE CABO VERDE ISLANDS... ...TROPICAL STORM WARNING ISSUED FOR THE CABO VERDE ISLANDS... SUMMARY OF 200 AM CVT...0300 UTC...INFORMATION ---------------------------------------------- LOCATION...13.2N 22.1W ABOUT 190 MI...305 KM SE OF THE SOUTHERNMOST CABO VERDE ISLANDS MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...NNW OR 330 DEGREES AT 8 MPH...13 KM/H MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: The Government of the Cabo Verde Islands has issued a Tropical Storm Warning for all of the Cabo Verde Islands.

I took my first evening walk at the park of the season in lieu of the treadmill as a result of the cool and windy weather thanks to the strong wedge. It was only in the mid 60s along with winds gusting as high as ~25 mph. Due to dewpoints of 60, the RH was high. But the wind combined with the coolness made it feel great! Also, there was intermittent drizzle, which was unexpected and made it feel even cooler.

Check out the 12Z UKMET: gets her all the way to 23.7N, 56.4W and still moving WSW not too far N of the MDR: TROPICAL STORM FAY ANALYSED POSITION : 30.0N 41.2W ATCF IDENTIFIER : AL062026 LEAD CENTRAL MAXIMUM WIND VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS) -------------- ---- -------- ------------- ------------- 1200UTC 24.09.2026 0 30.0N 41.2W 1014 28 0000UTC 25.09.2026 12 30.2N 42.1W 1015 25 1200UTC 25.09.2026 24 30.3N 43.1W 1015 27 0000UTC 26.09.2026 36 30.3N 43.7W 1015 25 1200UTC 26.09.2026 48 30.2N 44.4W 1014 26 0000UTC 27.09.2026 60 30.2N 44.8W 1016 21 1200UTC 27.09.2026 72 30.1N 44.8W 1015 22 0000UTC 28.09.2026 84 29.8N 44.6W 1016 20 1200UTC 28.09.2026 96 28.6N 44.9W 1016 22 0000UTC 29.09.2026 108 27.4N 46.0W 1014 23 1200UTC 29.09.2026 120 26.2N 47.6W 1013 24 0000UTC 30.09.2026 132 24.9N 49.6W 1012 26 1200UTC 30.09.2026 144 24.2N 52.0W 1011 29 0000UTC 01.10.2026 156 23.8N 54.3W 1011 27 1200UTC 01.10.2026 168 23.7N 56.4W 1012 27

This is for Nolo, which is a threat to the Big Island of Hawaii: 000 WTPA42 PHFO 241450 TCDCP2 Tropical Storm Nolo Discussion Number 16 NWS Central Pacific Hurricane Center Honolulu HI EP152026 Issued by NWS National Hurricane Center Miami FL 500 AM HST Thu Sep 24 2026 Satellite images indicate that Nolo is gradually becoming better organized, with very deep convection in a curved band on the southern and western side of the circulation. Additionally, a GPM pass from overnight indicated that an inner core is forming, although the eastern side is fragmented. Intensity estimates are rising, and the current wind speed is set to 50 kt as a blend of the lower subjective and higher objective values. Nolo has not moved much during the last several hours but should begin to move northward and north-northeastward later today due to a mid-latitude trough dropping over the northwestern Hawaiian Islands. The trough is forecast to move westward by Saturday with a building ridge north of the main Hawaiian Islands, causing a sharp westward turn this weekend. The big question is how close does Nolo get before making that turn, with notable run-to-run inconsistencies in much of the guidance. Similar to the last cycle, the bulk of the models have shifted slightly northward, and the new NHC forecast is moved in that direction. This remains a more uncertain forecast than normal given the large unresolved north-south spread, with other possible complicating terrain influences of the Big Island (like we saw with Hurricane Lala last month). Therefore, the long-range portion of the forecast is essentially unchanged. With the formation of an inner core, conditions appear to be coming together for rapid intensification given the other conducive environmental factors of warm SSTs, low shear and high mid-level moisture. Nolo is likely to become a hurricane by tonight and reach major hurricane strength as it nears the Big Island on Saturday. The new forecast is raised from the previous one, just below the HCCA aid, which has done well this year in these strengthening episodes. Note that a track closer to the Big Island could substantially increase the threat of damaging winds, particularly over higher terrain, along exposed ridges, and in areas downwind of the ridges. FORECAST POSITIONS AND MAX WINDS INIT 24/1500Z 14.9N 156.2W 50 KT 60 MPH 12H 25/0000Z 15.2N 156.2W 65 KT 75 MPH 24H 25/1200Z 16.1N 155.8W 80 KT 90 MPH 36H 26/0000Z 17.1N 155.4W 95 KT 110 MPH 48H 26/1200Z 17.8N 155.4W 100 KT 115 MPH 60H 27/0000Z 18.0N 156.4W 105 KT 120 MPH 72H 27/1200Z 18.1N 158.2W 105 KT 120 MPH 96H 28/1200Z 19.0N 162.0W 105 KT 120 MPH 120H 29/1200Z 21.6N 164.4W 90 KT 105 MPH $$ Forecaster Blake

From NHC: Resilient Fay has strengthened this morning. Deep convective curved bands have developed both on the west and east sides of the cyclone, and a small cold cloud top deep burst of convection is persisting over the surface center. Based on the improved cloud pattern and an increase in the Dvorak satellite intensity estimated from TAFB, the initial intensity is raised to 45 kt. Fay remains over warm ocean waters and a favorable upper-level wind environment. Only a relatively stable, dry surrounding atmosphere is preventing Fay from strengthening significantly. By the weekend, deep-layer shear is expected to increase, which should induce a weakening trend. Subsequently, Fay is forecast to degenerate into a remnant low. Fay's initial motion is estimated to be due west, or 270/5 kt. This general motion should continue with a slight reduction in forward speed through dissipation on Sunday. The NHC track forecast is similar to the previous advisory and lies close to the skilled HFIP HCCA and GDMI TC ensemble mean. FORECAST POSITIONS AND MAX WINDS INIT 24/1500Z 29.8N 41.2W 45 KT 50 MPH 12H 25/0000Z 29.8N 42.0W 50 KT 60 MPH 24H 25/1200Z 29.7N 42.9W 45 KT 50 MPH 36H 26/0000Z 29.6N 43.9W 40 KT 45 MPH 48H 26/1200Z 29.5N 45.2W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 27/0000Z 29.5N 46.0W 30 KT 35 MPH...POST-TROP/REMNT LOW 72H 27/1200Z...DISSIPATED $$ Forecaster Roberts

When was the comparable last nasty cold core nor’easter that occurred in your area as early as late Sept? The ones I recall off the top of my head for your area waited at least til Oct and were mainly in the latter half of Oct to boot.

*Fwiw* recent 3 day (12 run) CFSv2 runs for Feb have been cooling back down again. The coldest I’ve seen was the very cold Aug 7-9th mean. The warmest was the recently posted Sep 16-18th mean. The newest (Sep 21-23rd) is right in between those:

Thanks. Do you see it having a chance to transition from cold core, which we all agree it will start as, to ST status?

Then the NHC should be adding it to its TWOs since those address the chance for both T and ST development. Adding it to its TWOs has been suggested by both JB and @vortex95

This from the 0Z Euro suite per pro met@vortex95shows a 70-80% chance for tropical development! How do you explain this?

0Z UKMET goes NNE to eastern end of LI and then into SE New England while weakening substantially Mon-Tue

Thanks. But how do you explain a 1000/500 mb thickness max of >576 dm and 700 mb height max both at the center if it is cold core? That almost has to be warm core.

Joe Bastardi, who I often don’t agree with, continues to insist this will transition from baroclinic/cold core to warm core Fri night/early Sat leading to an “eye-like feature” and says it thus should be named. He says the NHC is wrong in not even putting it in its TWOs. He shows the Euro ensemble giving it a 70% chance for tropical development. He said there will be rapid feedback over SSTs that are abnormally warm (well above 79F) due largely to GW. Per JB, evidence of it being warm-core is that it starts to weaken as it moves NW into cooler SSTs followed by it dissipating as it makes landfall. Also, he posted the Euro having a warm center offshore on Sun AM at 700 mb! He shows 1000/500 mb thicknesses peaking at the center at >576 dm! He compares this projected weakening over cooler SSTs to Henri of ‘21 as it approached the NE. He said tides may go as high as 3-6 feet AN at NYC! Does anyone here recall a purely cold-core nor’easter in this region this early in the fall? Aren’t those usually not til Oct, when SSTs aren’t as warm?