bluewave

Return to more comfortable temperatures next week into late August as the Erin recurve merges with the trough and keeps the 500 mb heights lower over the Northeast. August 18-25 August 25-31

Familiar pattern in recent years as the all-time record heat went to our north in Canada.

While we are only 6 summers into the 2020s, it’s been significantly warmer than the Philly to Newark corridor was back in the 1990s. If we continue this level of summer warmth for the next 4 summers, then it will have the highest number of 90° days on record. The previous leader for 90° days was the 2010s. Philly to Newark corridor average annual number of 90° days by decade 2020s….Philly….35…..Hightstown….39…..Newark….36 2010s…. 34….33…32 2000s….23…..21…23 1990s…..31…..20…29 1980s…..26….21….26 1970s……22….14….20 1960s……17…..20….21 1950s…..26……23…25 1940s…..26…..23….25

The record high of 98° at Augusta, Maine was two degrees under the August all-time high. They got the all-time June monthly record earlier this summer. Through August 11th this has been their driest summer on record. Also their first year reaching 98° or higher twice. Time Series Summary for AUGUSTA STATE AIRPORT, ME - Month of Aug Warmest High Temperature Click column heading to sort ascending, click again to sort descending. 1 1955 100 0 2 2025 98 20 - 1948 98 0 3 2001 97 0 - 1975 97 0 4 2002 96 0 - 1987 96 0 5 1953 95 0 - 1949 95 0 Time Series Summary for AUGUSTA STATE AIRPORT, ME - Month of Jun Click column heading to sort ascending, click again to sort descending. 1 2025 100 0 2 1995 98 0 3 2024 97 0 - 1988 97 0 - 1971 97 0 4 1955 95 0 - 1953 95 0 5 2021 94 0 - 2020 94 0 - 2005 94 0 - 1984 94 0 - 1963 94 0 - 1956 94 0 Time Series Summary for AUGUSTA STATE AIRPORT, ME June 1st through August 11th Lowest Rainfall Click column heading to sort ascending, click again to sort descending. 1 2025-08-11 3.00 3 2 1999-08-11 3.57 0 3 1949-08-11 3.80 0 4 1994-08-11 3.82 0 5 1952-08-11 4.31 0 6 2017-08-11 4.77 0 7 1965-08-11 4.80 0 8 1995-08-11 4.81 0 9 1950-08-11 5.06 0 10 1966-08-11 5.15 0

Both urban and rural NJ sections weren’t consistently as warm as they have been since 2010. Getting 30+ and 40+ days reaching 90° only happened from time to time with many cooler seasons under 20 days and even 10 days. These days most of the seasons are over 30 days with the cooler seasons under 20 or 10 days hard to come by anymore.

JFK has had nearly as many record and near record highs as Newark in the fall during recent years even though it’s a much cooler location. JFK had record heat into early November last year with the developing drought. So fall record heat has been a constant in recent years. JFK September and October numerous near and record highs since 2015 9/1 92 in 2012 92 in 2010 91 in 1969+ 9/2 93 in 1973 93 in 1961 93 in 1953 9/3 93 in 2015 93 in 1993 92 in 1957 9/4 93 in 2018 93 in 1985 92 in 1961 9/5 94 in 1961 93 in 2023 92 in 1985+ 9/6 93 in 2023 92 in 1985 90 in 1998+ 9/7 93 in 1983 92 in 2023 92 in 1978 9/8 92 in 2010 91 in 2015 87 in 2013+ 9/9 93 in 1959 91 in 2016 88 in 1964 9/10 98 in 1983 92 in 1989 90 in 1961 9/11 96 in 1983 91 in 1989 89 in 1961 9/12 91 in 1981 90 in 2005 90 in 1952 9/13 94 in 1952 89 in 1994 89 in 1957 9/14 89 in 1995 89 in 1972 88 in 1981+ 9/15 85 in 2008 82 in 2009 82 in 1997+ 9/16 89 in 1991 88 in 1998 88 in 1970 9/17 90 in 1991 84 in 2015 84 in 1969 9/18 90 in 1965 86 in 2021 86 in 1964+ 9/19 90 in 1983 87 in 2024 85 in 2022+ 9/20 85 in 1997 85 in 1983 84 in 2024 9/21 85 in 2016 83 in 2004 83 in 1989 9/22 91 in 1980 87 in 1961 86 in 1970 9/23 90 in 1970 89 in 1961 88 in 2017+ 9/24 92 in 2017 88 in 1970 86 in 1961 9/25 87 in 2010 85 in 2017 83 in 2011 9/26 87 in 1970 85 in 1958 82 in 1968 9/27 89 in 1998 87 in 2017 84 in 2014+ 9/28 82 in 1948 81 in 1961 81 in 1959+ 9/29 82 in 1948 81 in 2019 81 in 1959 9/30 84 in 1986 82 in 1959 80 in 1971+ 10/1 85 in 1986 84 in 1954 84 in 1950 10/2 95 in 2019 85 in 2013 82 in 2002+ 10/3 84 in 2002 82 in 2000 81 in 1969 10/4 84 in 1967 83 in 1959 83 in 1954 10/5 84 in 1967 83 in 2017 83 in 2002+ 10/6 88 in 1997 85 in 1995 83 in 1959 10/7 83 in 2007 83 in 1961 82 in 1997 10/8 90 in 2007 78 in 1959 77 in 2021 10/9 87 in 2011 82 in 1961 82 in 1959 10/10 86 in 1997 84 in 2017 84 in 2011 10/11 80 in 1960 77 in 2017 77 in 1969+ 10/12 83 in 1969 81 in 1962 79 in 1995+ 10/13 79 in 1995 78 in 2008 77 in 1989 10/14 82 in 1990 82 in 1975 80 in 2021 10/15 82 in 1975 79 in 2000 78 in 1990 10/16 79 in 2008 77 in 1964 76 in 1963 10/17 82 in 1963 76 in 1996 75 in 2016+ 10/18 77 in 1964 75 in 2016 75 in 2006 10/19 86 in 2016 75 in 1965 74 in 1998+ 10/20 81 in 1969 79 in 2021 79 in 1984 10/21 81 in 1963 80 in 1949 78 in 2024 10/22 80 in 2024 77 in 1984 77 in 1975 10/23 77 in 1978 74 in 2007 73 in 2017 10/24 74 in 2017 73 in 2001 72 in 2024+ 10/25 77 in 2001 73 in 2022 73 in 2021+ 10/26 78 in 1971 75 in 1989 75 in 1963 10/27 78 in 1963 75 in 1989 73 in 1964 10/28 81 in 2023 76 in 2010 75 in 1989+ 10/29 80 in 1971 74 in 2015 74 in 2014+ 10/30 79 in 1961 77 in 1950 73 in 2024+ 10/31 78 in 2024 75 in 1950 74 in 2004+ 11/1 82 in 2024 80 in 1950 77 in 1982

The warm spots like Newark have had plenty of September and October record heat in recent years. Just notice all the records and near records since 2015. This is why the tropical system tracks are going to be so important as we head into the fall. Since parts of the area have had their driest summer on record so far. We will need an assist from the tropics in either lowering heights or providing rainfall. If one or both of these factors fail to materialize, then there is nothing stopping more heat and ridging into the fall with an expansion of drought. Newark September and October record and near record highs since 2015 9/4 95 in 2018 95 in 1973 95 in 1964 9/5 95 in 2023 94 in 1985 94 in 1961 9/6 98 in 2018 97 in 2023 97 in 1983 9/7 96 in 2023 95 in 2015 93 in 2010 9/8 98 in 2015 94 in 1939 93 in 2010+ 9/9 94 in 1964 93 in 2016 92 in 1971+ 9/10 98 in 1983 97 in 1989 95 in 1931 9/11 99 in 1983 96 in 2013 96 in 1964+ 9/12 95 in 1961 93 in 2005 90 in 1952+ 9/13 94 in 2005 94 in 1952 93 in 1957+ 9/14 94 in 2016 92 in 2008 92 in 1931 9/15 94 in 1993 91 in 2021 91 in 1942 9/16 95 in 1991 92 in 1970 91 in 1958+ 9/17 95 in 1991 93 in 1972 91 in 1994 9/18 90 in 1992 90 in 1948 89 in 1965 9/19 93 in 1983 89 in 1946 88 in 2022+ 9/20 92 in 1983 88 in 1946 87 in 1985 9/21 90 in 1940 88 in 1998 88 in 1980 9/22 94 in 1970 93 in 1931 92 in 1980 9/23 94 in 1970 93 in 2019 93 in 1959 9/24 92 in 2017 92 in 1959 89 in 1970 9/25 91 in 1970 90 in 2017 90 in 2010+ 9/26 90 in 2007 90 in 1958 88 in 1970 9/27 91 in 1998 89 in 1933 88 in 2017 9/28 87 in 2014 86 in 2019 85 in 1954+ 9/29 89 in 1945 83 in 1959 82 in 2015+ 9/30 89 in 1986 85 in 1954 82 in 1960+ 10/1 85 in 1986 85 in 1950 84 in 2019+ 10/2 96 in 2019 86 in 2013 86 in 2002+ 10/3 85 in 2023 85 in 1950 84 in 2021+ 10/4 89 in 2013 87 in 2007 87 in 1959 10/5 93 in 1941 87 in 1967 86 in 2017 10/6 91 in 1959 90 in 1941 88 in 1997+ 10/7 88 in 1944 87 in 1946 85 in 1990 10/8 89 in 2007 85 in 1931 84 in 1990 10/9 88 in 2011 87 in 1990 86 in 1959+ 10/10 92 in 1949 90 in 1939 86 in 1958 10/11 88 in 1949 85 in 1954 83 in 1955 10/12 88 in 1954 86 in 1962 85 in 1949 10/13 89 in 1954 85 in 1995 83 in 1978 10/14 85 in 1975 83 in 1990 82 in 2021 10/15 86 in 1956 85 in 1960 84 in 2021+ 10/16 84 in 1958 83 in 1992 83 in 1963 10/17 90 in 1938 83 in 2016 82 in 1963 10/18 85 in 2016 80 in 1964 79 in 2007+ 10/19 87 in 2016 82 in 1945 81 in 1963 10/20 80 in 2021 80 in 1969 80 in 1947 10/21 84 in 2024 84 in 1947 81 in 2017 10/22 86 in 1979 83 in 2024 79 in 1984+ 10/23 87 in 1947 82 in 2024 82 in 1978 10/24 83 in 2001 78 in 1946 77 in 2017+ 10/25 79 in 2001 79 in 1963 78 in 2021 10/26 82 in 2023 79 in 1964 79 in 1963 10/27 81 in 1963 80 in 1947 78 in 2023+ 10/28 84 in 2023 82 in 1984 78 in 1989+ 10/29 78 in 1971 78 in 1946 76 in 1989 10/30 82 in 1946 80 in 1961 80 in 1950 10/31 83 in 2024 82 in 1946 79 in 1950

Yeah, the record SST warmth near the Maritime Continent has been leading to significantly more -IODs over time than we used to get.

It was pretty much wall to wall heat and ridging from June 21st through July 31st. We got a relaxation of this pattern for the first week of August. This current heat wave is a weaker reflection of what we got back in June and July. So the shift in the modeling for next week is the hurricane lowering heights in the East as it recurves west of Bermuda. Would like to see some improvement in the rainfall situation. Since we have seen time and time again how heat has remerged in September into October during dry patterns. We would at least need to keep the tropics active in Atlantic to have a shot at avoiding potential fall record heat when the pattern has been so dry.

Hopefully, we can get the Erin recurve west of Bermuda next week so the WAR gets weakened enough. Big shift to cooler on the EPS for the 18-25. Now the models have a trough along the East Coast instead of a ridge. Longer range will continue to be about the tropics. If we keep getting troughs in the East and tropical systems moving into the weakness, then maybe we can avoid 95+ heat after August 20th. But if the tropical moisture remains east, then the drought conditions will continue expanding. It’s already been the driest summer on record for spots like BDR. The tropics will continue to be the wild card into September. Since a continuing dry pattern and any lack of tropical systems and Eastern trough would allow the ridge to expand again. So the pattern could be mid-August warmth…late August closer to average…early September rebound in temperatures if we stay dry. But enhanced tropical activity in early September could push back against the heat by lowering heights over the Western Atlantic. Cooler trends for August 18-25 New runs Old runs

All the warm spots from Philly to Corona, Queens are pretty uniform around 30 days reaching 90°. 90° days for 2025 so far Philly…30 Highstown…32 TEB…31 EWR…33 Harrison….30 Corona…27

Warmer than areas to the east like Long Island which get regular cooling sea breezes. A few NJ COOP sites have been warmer recently. Harrison has been pretty close. NJ just happens to be a very warm area away from the sea breeze. Data for June 21, 2025 through July 31, 2025 Average Maximum Temperarure Click column heading to sort ascending, click again to sort descending. SEABROOK FARMS COOP 92.8 INDIAN MILLS 2 W COOP 92.6 NEWARK LIBERTY INTL AP WBAN 91.5 Newark Area ThreadEx 91.5 HARRISON COOP 91.0 TETERBORO AIRPORT WBAN 90.7 OCEAN COUNTY AIRPORT WBAN 90.6 TETERBORO AIRPORT COOP 90.5 HIGHTSTOWN 2 W COOP 90.2 BELVIDERE BRIDGE COOP 90.0 Belvidere Area ThreadEx 90.0 map Data for June 21, 2025 through July 31, 2025 Maximum Temperature Click column heading to sort ascending, click again to sort descending. NEWARK LIBERTY INTL AP WBAN 103 HARRISON COOP 103 Newark Area ThreadEx 103 OCEAN COUNTY AIRPORT WBAN 103 ATLANTIC CITY INTL AP WBAN 102 INDIAN MILLS 2 W COOP 102 Atlantic City Area ThreadEx 102 MILLVILLE MUNICIPAL AIRPORT WBAN 101 LONG BRANCH-OAKHURST COOP 101 CANOE BROOK COOP 101 TETERBORO AIRPORT WBAN 101 CALDWELL ESSEX COUNTY AP WBAN 101 ESTELL MANOR COOP 101 TETERBORO AIRPORT COOP 101 SEABROOK FARMS COOP 100 HIGHTSTOWN 2 W COOP 100 NEW BRUNSWICK 3 SE COOP 100 SOUTH JERSEY REGIONAL AIRPORT WBAN 100 SOMERSET AIRPORT WBAN 100 PHILADELPHIA/MT. HOLLY WFO COOP 100 SALEM COOP 100 EB FORSYTHE NEW JERSEY RAWS 100 PENNSAUKEN 1N COOP 100

This Kara-Barents or Urals ridge has become the most impressive Arctic 500mb height anomaly since the sea ice shift to much lower in 2007 with a new lowest maximum in March 2025.

Nice improvements in the temperature department on the 0z runs. The models get Erin back to near 70W off the Carolinas. So it erodes the ridge and lowers the 500mb heights. This causes the current warm pattern to end by early next week. Tropical systems are often the wild card for us after mid-August heatwaves. They can stay offshore like the current guidance shows and still weaken the WAR or Southeast Ridge. The new runs now have lower heights in the East in just 12 hours. So we need later runs to get the storm back near 70W for the relaxation of the heat to continue. Remember, the long range pattern all summer has been to build heights higher than the original forecasts. But it often takes a tropical system to disrupt heat patterns along the East Coast this time of year. New run Old run New run Old run

Brown lawns across the CT Shoreline as BDR is working on their #1 driest summer on record and 6th warmest. Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT Driest June 1st through August 9th Click column heading to sort ascending, click again to sort descending. 1 2025-08-09 2.34 0 2 1966-08-09 2.58 0 3 1999-08-09 2.72 0 4 1993-08-09 3.06 0 5 1964-08-09 3.37 0 6 1957-08-09 3.84 0 7 1994-08-09 3.99 0 8 1995-08-09 4.01 0 9 1955-08-09 4.08 0 10 1970-08-09 4.11 0 Time Series Summary for IGOR I SIKORSKY MEMORIAL AIRPORT, CT Warmest June 1st Through August 9th Click column heading to sort ascending, click again to sort descending. 1 2010-08-09 75.3 0 2 2020-08-09 75.2 0 3 2024-08-09 75.1 0 4 1994-08-09 75.0 0 5 2008-08-09 74.4 0 6 2025-08-09 74.3 0 7 2019-08-09 74.2 0 - 2016-08-09 74.2 0 - 2012-08-09 74.2 0 - 2011-08-09 74.2 0 - 1949-08-09 74.2 0 8 2013-08-09 74.1 0 9 2022-08-09 74.0 0 - 1999-08-09 74.0 0 10 1993-08-09 73.7 0 CT ANSONIA 1 NW COOP 2.20 CT IGOR I SIKORSKY MEMORIAL AIRPORT WBAN 2.34 NY BAYPORT 1.0 SSE CoCoRaHS 2.40 NJ HAWTHORNE 1.0 SSE CoCoRaHS 2.75 NJ RIVER VALE TWP 1.5 S CoCoRaHS 2.84 NJ CEDAR GROVE TWP 0.4 W CoCoRaHS 2.84 NY SHELTER ISLAND HEIGHTS 2.1 SSW CoCoRaHS 2.95 NY SAYVILLE 0.0 N CoCoRaHS 2.96 CT FAIRFIELD 1.5 NE CoCoRaHS 3.01 CT STRATFORD 0.9 W CoCoRaHS 3.05 CT GUILFORD CENTER 2.7 WSW CoCoRaHS 3.11 CT WATERFORD 2.3 S CoCoRaHS 3.17 CT WALLINGFORD CENTER 1.1 N CoCoRaHS 3.18

I guess the one piece of good news is that the original idea of the heat not rivaling the June and July widespread 100°+ temperatures will turn out to be correct this week. Since the models keep a very strong onshore flow influence. So maybe there could be a few local highs near 100° away from the sea breeze in NJ. But not the 103°-105° max heat of June and the 101°-103° max heat back in July. So at least we are making some progress in the right direction. But if we keep missing rainfall opportunities, then more 90°+ heat will be possible from time to time through September and maybe even into October. The big question is if the usual warm spots like Newark can get their first 100° after August 15th since 1993. That has been a tough record to beat. But it could only be a matter of time if one of these flash soil moisture type droughts overperforms.

It’s possible that the strongest polar blocking since the 2007 Arctic sea ice decline has been back closer to the Barents and Kara seas due to the open waters in those locations during the winter. Maybe the Arctic winter pattern from 2007-2025 has been some type of open water SST feedback ridge where there used to be thick ice during the winter. The older blocking intervals used to have the blocking focused closer to Greenland. The last 18 winters have had the blocking centered from the KB areas to the pole instead. So this could be making the blocking more AO dominant instead of NAO focused.

Much easier for JFK to go 10 days with minimums staying at or above 70°. Number of Consecutive Days Min Temperature >= 70 for JFK INTERNATIONAL AIRPORT, NY Click column heading to sort ascending, click again to sort descending. 1 29 1980-07-16 through 1980-08-13 2 24 2013-07-01 through 2013-07-24 - 24 1995-07-13 through 1995-08-05 3 21 2010-07-05 through 2010-07-25 - 21 1988-07-28 through 1988-08-17 4 20 2023-07-03 through 2023-07-22 5 19 2020-07-18 through 2020-08-05 6 18 1999-07-17 through 1999-08-03 7 17 1984-08-01 through 1984-08-17 8 16 2025-07-06 through 2025-07-21 - 16 2003-08-01 through 2003-08-16 9 15 1979-07-23 through 1979-08-06 10 14 2024-07-05 through 2024-07-18 - 14 2022-07-13 through 2022-07-26 - 14 2016-08-08 through 2016-08-21 - 14 2005-08-02 through 2005-08-15 - 14 1972-07-14 through 1972-07-27 - 14 1969-07-28 through 1969-08-10 11 13 2012-06-29 through 2012-07-11 - 13 1983-07-28 through 1983-08-09 - 13 1978-08-06 through 1978-08-18 12 12 2019-07-27 through 2019-08-07 - 12 2016-07-21 through 2016-08-01 - 12 2015-07-25 through 2015-08-05 - 12 1993-07-04 through 1993-07-15 - 12 1955-07-16 through 1955-07-27 - 12 1952-07-13 through 1952-07-24 - 12 1949-07-12 through 1949-07-23 13 11 2021-08-17 through 2021-08-27 - 11 2020-07-05 through 2020-07-15 - 11 2009-08-16 through 2009-08-26 - 11 1994-07-25 through 1994-08-04 - 11 1973-08-27 through 1973-09-06 - 11 1970-07-24 through 1970-08-03 - 11 1959-08-12 through 1959-08-22 - 11 1955-08-13 through 1955-08-23 - 11 1953-08-27 through 1953-09-06 14 10 2022-08-03 through 2022-08-12 - 10 2011-07-17 through 2011-07-26 - 10 2007-07-26 through 2007-08-04 - 10 2006-07-26 through 2006-08-04 - 10 2005-07-14 through 2005-07-23 - 10 1993-08-25 through 1993-09-03 - 10 1991-07-17 through 1991-07-26 - 10 1987-07-19 through 1987-07-28 - 10 1983-07-12 through 1983-07-21 - 10 1971-09-03 through 1971-09-12 - 10 1959-08-27 through 1959-09-05 - 10 1949-08-03 through 1949-08-12

That was 10-22-79 when there weren’t trees over the NYC ASOS. The warm spots in NYC made it to 90°. One spot in NJ made it to 88°. So that 87° at SMQ last year was the warmest so late for that station. But just behind Plainfield for the state record. Data for October 22, 1979 through October 22, 1979 Click column heading to sort ascending, click again to sort descending. NY NEW YORK LAUREL HILL COOP 90 NJ PLAINFIELD COOP 88 NY NY CITY CENTRAL PARK WBAN 88 NJ CRANFORD COOP 87 NY NY WESTERLEIGH STAT IS COOP 87 NY WEST POINT COOP 86 CT STAMFORD 5 N COOP 86 CT DANBURY COOP 86 NJ NEWARK LIBERTY INTL AP WBAN 86

Several spots only got a T to .01. But it goes to show how quickly we can get to record heat when we get dry in the much warmer climate. SMQ made it to 87° last October 22nd. That was the latest 87° in the year that SMQ was that warm. If that flash drought started over the summer and lasted into October, then 90° would have been possible. Data for October 22, 2024 through October 22, 2024 Click column heading to sort ascending, click again to sort descending. SOMERSET AIRPORT WBAN 87 INDIAN MILLS 2 W COOP 85 NEW BRUNSWICK 3 SE COOP 85 SOUTH JERSEY REGIONAL AIRPORT WBAN 85 SUSSEX AIRPORT WBAN 85 New Brunswick Area ThreadEx 85

The warm spots in NJ had 2 separate 10 day heatwaves back in July and August of 2022. But you need to be west of the sea breeze front in NJ to open up multiple 10 day runs in the same season. The last 20 day heatwave in NJ was back in 1988. So 10 day heatwaves aren’t that big of a deal for the warm areas. But it’s very difficult east of the Hudson due to the enhanced sea breeze circulations in recent years. Plus the tree growth shading the NYC ASOS prevents 10 day heatwaves there. Number of Consecutive Days Max Temperature >= 90 for HIGHTSTOWN 2 W, NJ Click column heading to sort ascending, click again to sort descending. 1 14 1995-07-24 through 1995-08-06 2 12 1953-08-25 through 1953-09-05 3 11 1999-07-24 through 1999-08-03 4 10 2022-08-03 through 2022-08-12 - 10 2022-07-17 through 2022-07-26

Really erratic rainfall pattern during the 2020s so far. Most of the months are either well above or well below on the rainfall. Not much balance. Monthly Total Precipitation for NY CITY CENTRAL PARK, NY Click column heading to sort ascending, click again to sort descending. 2025 0.61 2.60 5.52 3.25 6.58 2.46 4.03 0.06 M M M M 25.11 2024 5.28 2.05 9.06 3.47 4.11 1.71 4.20 7.02 1.58 0.01 3.35 4.53 46.37 2023 4.38 1.28 3.32 7.70 1.28 1.62 5.34 6.56 14.25 3.90 2.95 6.71 59.29 2022 4.29 3.23 2.39 4.53 4.52 2.92 4.55 1.71 4.10 5.08 3.15 5.83 46.30 2021 2.31 5.13 3.41 2.69 4.36 2.62 11.09 10.32 10.03 5.26 1.12 1.39 59.73 2020 1.93 2.54 3.78 4.49 1.65 1.76 6.58 5.03 3.94 5.05 3.99 4.61 45.35

Both the 16-17 and 17-18 seasons were better around the NYC Metro coastal areas the further east on Long Island that you were. Same went for January 22 with spots from ACY to Suffolk County on Long Island doing better. 07-08, 06-07, and 01-02 were the 3 lowest snowfall seasons for the 2000s in my area. The good snowfall seasons were 00-01, 02-03, 03-04, 04-05, 05-06, and 08-09.

All the models agree on the warm spots starting the heatwave today through Wednesday. Then we get a front coming through on Thursday. But the GFS is the only model with much rainfall so it gets cooler for a few days before the 90s return by next Monday. The Euro and CMC don’t have much rainfall so the Euro brings the heat back faster. The Euro doesn’t dip much below 90° later this week at the NJ warm spots before the heat reloads again by next Sunday or Monday. The issue continues to be lack of rainfall. If we don’t see much rain later this week, then there is nothing stopping the heat from returning again in a week. If we can score some rainfall and cooler temperatures this Thursday and Friday, then we’ll get two separate heatwaves rather than a continuous one at the usual NJ warm spots. But as long as we continue to stay dry, the ridges keep reloading and we keep getting the heat.

You would want to eventually see a wetter pattern develop in order to push back against the heat. If we continue to stay this dry, then there is nothing stopping us from having heatwaves right into September or maybe even October. The tropics may turn out to be a wild card going forward. If we find a way to avoid any PREs and even some remnant tropical moisture, then we could be looking at another late summer and fall drought developing. Long range rainfall forecasting is often low skill. But the one constant is that heat will quickly dry things out when there isn’t any rain. During the cooler summers in the past, we could get by with less rain.