bluewave

The Southeast ridge has become a big player since the 15-16 super El Niño. New run Old run

Yeah, these -NAO patterns have been changing in recent years. They have tended to link up with the Southeast ridge more. My guess is that it’s related to the record Atlantic SSTs and possibly other marine heatwaves across the planet. We have seen how models have been underestimating this factor longer range. So storm systems start out days 6-10 more suppressed and colder only to correct more north or northwest and warmer under 5 days. I know people follow the model headline scores for the Northern Hemisphere. But this issue near the East Coast isn’t something that shows up in these model forecast statistics. So we have to take this model bias into account when looking at longer range forecasts.

Models feeling the stronger Southeast ridge now so the 0z guidance came further north. Same northward correction we have been seeing all winter. The good news now is that it’s April and most people would want a warmer solution. So a continuation of the -NAO linking up with the Southeast ridge. Also a trend to deeper primary so the secondary isn’t nearly as strong as in earlier runs. Still a good soaker for the area but with a less intense low pressure. New run Old run

Yeah, the Euro tropical forecast from March 5th was already the strongest for so early in the season. So the update coming on April 5th should be interesting. All-time Atlantic SST warmth for so early on the season coupled with a strong La Niña signal.

It got to 36° for a high. 1923-04-01 36 12

Our climate has warmed way too much to ever see April cold like that again. Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Min Temperature Missing Count 1 1923 12 0 2 1874 20 0 3 1982 21 0 - 1881 21 0 4 1919 22 0 - 1875 22 1 5 1995 23 0 - 1954 23 0 Time Series Summary for NY CITY CENTRAL PARK, NY - Month of Apr Click column heading to sort ascending, click again to sort descending. Rank Year Lowest Max Temperature Missing Count 1 1982 30 0 - 1881 30 0 2 1879 32 0 - 1875 32 1 3 1938 33 0 4 1944 34 0 - 1943 34 0 - 1896 34 0 - 1874 34 0 5 1940 35 0 - 1918 35 0 - 1911 35 0 - 1870 35 1

Our climate is much too warm now to ever see Arctic cold like that again in April.

Not close since that had a 100 year Arctic outbreak in April which was the last time NYC set 3 consecutive low temperatures. It was also the last time NYC had afternoon temperatures in April in the 20s. That was the tail end of the mini ice age we had in the late 70s before our temperatures really began to take off.

The block is so strong since we recently saw the big PV disruption. Then we got the tropics on board with the MJO 8-1 followed by the wave break. The reason the mountains are favored this time around is that it’s so much warmer than 1996,2003, and 2018. Plus the seasonal storm tracks those years were much more favorable for us.

Yeah, I think we still would have had P-Type issues near the coast even in January since the Southeast ridge is forecast to be very strong a day before the storm next week. This allows the primary to ride pretty far north before the coastal eventually takes over. So a continuation of these -NAOs and -AOs linking up with the WAR or Southeast ridge.

I started the general April thread to discuss that storm potential for the first week of April.

Unusually amplified start to April with one of the strongest west based blocks that we have seen in early April. Models indicating the potential for a +4 to +5 SD 500 mb block near Greenland. This is followed by a deep upper low and storm system crossing the Northeast approaching -4 SD. So more heavy rains and strong winds possible for our area with a late season higher elevation snow threat for portions of the Northeast.

Hopefully, the EPS high pressure forecast works out for the 8th.

Could be another nice event for the ski resorts.

Some thunderstorms earlier in that batch.

Not surprising given the continuing record WAR and SE Ridge patterns since the 15-16 super El Niño. Near to record 500mb heights for Canadian Maritimes

I am hoping the EPS idea of the pattern drying out during the eclipse week is correct. But a daily forecast that far out will always be low skill.

Parts of the area could go over 12.00 on the month with this event and a bunch over 10.00. Data for March 1, 2024 through March 27, 2024 Click column heading to sort ascending, click again to sort descending. State Name Station Type Total Precipitation NY SMITHTOWN 2.0 SSW CoCoRaHS 10.93 CT SALEM 3.6 SE CoCoRaHS 10.83 NY HOWARD BEACH 0.4 NNW CoCoRaHS 10.51 CT OAKDALE 2.6 WNW CoCoRaHS 10.46 CT NORWICH 2.5 NNE CoCoRaHS 10.34 CT STRATFORD 0.2 ESE CoCoRaHS 10.23 NY DEER PARK 1.0 NE CoCoRaHS 10.18 CT FAIRFIELD 1.5 NE CoCoRaHS 10.12 CT NORWICH 5.2 SE CoCoRaHS 10.05 NY ST. JAMES COOP 9.93 CT GUILFORD CENTER 2.7 WSW CoCoRaHS 9.93 CT STRATFORD 0.9 W CoCoRaHS 9.90 NY LITTLE NECK 0.3 SE CoCoRaHS 9.89 CT COLCHESTER 0.6 ENE CoCoRaHS 9.83 NY NORTHPORT 1.6 NNE CoCoRaHS 9.82 CT HIGGANUM 0.8 NE CoCoRaHS 9.80 NY BROOKLYN 3.1 NW CoCoRaHS 9.79 CT EAST LYME 0.5 SW CoCoRaHS 9.76 CT GUILFORD COOP 9.63 CT HIGGANUM 0.7 N CoCoRaHS 9.63 NY MANHASSET HILLS 0.2 NNE CoCoRaHS 9.59 CT NORTHFORD 0.8 SW CoCoRaHS 9.56 NY ALBERTSON 0.2 SSE CoCoRaHS 9.52 NY MALVERNE 0.5 SE CoCoRaHS 9.46 NJ MONTCLAIR 0.7 N CoCoRaHS 9.34 CT JEWETT CITY 3.0 ESE CoCoRaHS 9.31 NY CENTERPORT COOP 9.29 CT MIDDLEFIELD 1.4 W CoCoRaHS 9.27 CT MYSTIC 3.4 NW CoCoRaHS 9.24 NY CENTEREACH 1.3 NE CoCoRaHS 9.22 CT KILLINGWORTH 2.6 ESE CoCoRaHS 9.21 CT NEW CANAAN 1.9 ENE CoCoRaHS 9.20 NY SETAUKET-EAST SETAUKET 2.1 WNW CoCoRaHS 9.20 CT WALLINGFORD CENTER 1.9 WNW CoCoRaHS 9.20 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN 9.14 CT NORWALK 1.4 ENE CoCoRaHS 9.12 CT WALLINGFORD CENTER 3.3 NNW CoCoRaHS 9.11 CT ESSEX VILLAGE 0.9 S CoCoRaHS 9.11 NY WANTAGH 0.3 ESE CoCoRaHS 9.10

It least some of the higher elevations were able to reach average snowfall with the recent storm.

Yeah, strongest subsidence over the Maritime Continent for the whole year so far.

That 4 sigma 500 mb Greenland block in the forecast looks to be the strongest of the year so far. So a very active pattern will continue into early April. Spring will remain on hiatus for a while longer.

I guess the orientation of the marine heatwaves in the MJO 4-7 zones holds the convection there longer during the winter. Then the last 2 years the convection finally was able to shift at some point in March. Our last solid winter month here was Jan 22 when the MJO was able to linger in 8.

This blocking pattern going into April looks legit. MJO 8-1 is teaming up with a wave break for Greenland blocking. While the higher elevations are always favored for April snows, this is the type of pattern that could produce a trace that doesn’t accumulate much closer to the coast. I guess it would be like what happened in May 2020. Late season blocks have been becoming more common in recent years.

Approaching the middle of the pack for late March but lower than the record highs were seeing at this time last year.