{ "number": 968, "headline": "June 25, 2026 Eastern US Heat Dome Watch", "standfirst": "Thursday weather models trending toward more extreme temperatures into early July with widespread 90s and 100s", "desk": "record", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2026-06-26", "published": "2026-06-26T01:04:20.074000Z", "updated": null, "access": "free", "body_html": "
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Early summer evening with mostly tranquil weather across the Lower 48. A frontal boundary continues to fire storms from Oklahoma into mid-Mississippi River Valley. The main U.S. weather story will be a major heat dome building into July 4th.

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This is forecast post number 968: Day 176 of 2026. Day 25 of Atlantic Hurricane Season \u2014 so far very quiet with building El Ni\u00f1o.

Author: Dr. Ryan Maue (X @RyanWeather X @weathertrader)

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Upper-Level Height Anomaly | AIFS-Single Next 10-days

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While very strong troughing digs into the Pacific Northwest = much cooler air across the Western U.S. for perhaps 2-weeks, a major ridge forms over NE Arctic Canada and extends down an axis into the U.S. Southeast.

Ridging builds across the Eastern U.S. \u2014> dry and hot \u2014> HEAT DOME

Into Summer \u2014> Height Anomalies don\u2019t tell entire story \u2026 actual height helps!

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5940 m height contours \u2014 not quite record level near 6000 m but plenty of subsidence to ensure very hot surface temperatures. We\u2019re entering the \u201cdog days of summer\u201d when the weather pattern stagnates with long-lasting, slow moving ridges.

NWS Precipitation Next 72-hours \u2014> Sunday Afternoon

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Heavy rainfall will be focused on Kansas through Missouri, and into Illinois to Indianapolis with upgrades of 2\u201d to 4\u201d possible in just next few days.

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My favorite parameter \u2014 next 48-hours of HRRR Precipitable Water

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Weather Into Friday Morning

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Storms will continue across Oklahoma \u2014 with Moderate Risk according to SPC \u2014 of severe weather including tornadoes and large hail

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HRRR radar next 18-hours through Friday Noon ET

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HRRR Next 48-hours simulated Radar through Saturday 2 PM ET

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Plenty of moisture across the Lower 48 from the Pacific Northwest through the Rockies with some monsoon convection, and then quickly across the Ohio River Valley.

Weather on Friday \u2014 Stationary Front from Kansas City to D.C.

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Blend of Models \u2014> Precipitation Next 7-days

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Flagship model: ECMWF AIFS 18z \u2014> Integrated Vapor Transport next 10-days

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The magnitude of the tropical moisture feed into the USA from the Caribbean and Gulf is dialed down/back significantly as ridging strengthens over the Southeast U.S. \u2014> heat dome.

We can see the anticyclonic turning of the ridge centered over the southern Mississippi River Valley with limited moisture transport \u2014> really going to heat up for early July centered on North Carolina with subsidence over the Appalachians.

ECMWF AIFS 18z | Precipitable Water | My Favorite Parameter

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Generally 1.8\u201d (yellow) PWAT with embedded > 2\u201d convective cells but the heat dome really dials back the moisture coming out of the Gulf of Mexico. Perhaps this will be a \u201cdry heat\u201d

Temperature Analysis | RTMA | 7:30 PM ET

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About 37 million population at least 90\u00b0F at 7:30 PM ET but plenty of comfortable 70s blanketing the Lower 48 east of the Rockies.

Temperature Anomaly | RTMA | 7:30 PM ET

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Lower 48 was -2.9\u00b0F below normal behind the stationary front and within the clouds + rain cooled atmosphere in Nebraska

High Temperatures Next 9-Days \u2014> Saturday July 4th

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Trend to much hotter temperatures across the board into early July with 100s building across all of Texas with the much dryer conditions. Southeast including Atlanta and Carolinas push well into the 90s, and even 100s in the Carolinas.

With less tropical moisture plume activity from the Gulf of Mexico, we\u2019ll see much warmer temperatures and lower rain chances \u2014> warming trend into 4th of July.

Friday July 3rd Extreme Heat: 271 million at least 90\u00b0F and 38M > 100\u00b0F

Lower 48 spatial average high temperature almost 90\u00b0F

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107\u00b0F in Raleigh on Friday, July 3rd, and 100\u00b0F in Washington D.C.

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Saturday July 4th. Only slightly less hot!

Lower 48 Average High Temperature 89.3\u00b0F

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Next 10-days for Raleigh Durham \u2014> brutal with 102\u00b0 to 107\u00b0F for 4-5 days

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Washington D.C. with a pair of 100s

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Atlanta in the mid-90s but potential for much hotter as forecast comes closer

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NYC Central Park at 98\u00b0F on Thursday

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Low Temperatures on Friday

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Pretty comfortable across much of the Lower 48

High Temperatures on Friday

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114 at least 90\u00b0F

ECMWF Flagship Ensemble Mean Temperature Anomaly next 15-days

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Trough \u2014> cooler across the Pacific Northwest with huge negative anomalies of -20\u00b0F vs. the formation of a ridge into later June and HEAT across the Great Lakes and into the Mid-Atlantic + Canada

Week 1 \u2014> June 25 to July 1

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Week 2 \u2014> July 2 to July 8

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Pattern flip with trough in the NW and Western U.S. \u2014> cooler than normal with much warmer than normal into 4th of July east of the Rockies \u2014> trending HOTTER

Tropical Update: Atlantic Basin \u2014 Very Quiet into mid-July (15-day tracks forecast from EPS 12z)

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Global cyclone tracks (tropical + extratropical) over next 15-days

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Global cyclone tracks from ECMWF EPS 12z (ensembles) n=50-members

Western Pacific lights up with 2+ Typhoons likely with long-tracks = huge ACE

Light activity in Eastern Pacific. Complete ghost town in Atlantic basin

Note elsewhere around the world where cyclones just do not exist: between 0\u00b0S and 25\u00b0S in South Atlantic, huge void in Southeast Pacific, and the dominance of the North Pacific high + Bermuda high in North Atlantic.

Global Precipitation Anomaly next 2-weeks

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Central Pacific convection is \u201cboiling over\u201d with massive precipitation surplus falling along the Equator from South America to Papua New Guinea.

These showers trigger downstream Rossby waves and can help form \u201cheat domes\u201d or blocking ridges over North America and Europe.

\u2014> full tilt atmospheric coupling with ocean surface \u2014> El Ni\u00f1o

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My Atlantic Hurricane Season Forecast (2026)

From April 7, 2026: Atlantic Seasonal Hurricane Forecast: (11/5/2)

9-13 Named Storms (11 most likely)
4-7 Hurricanes (5 or 6 most likely)
1-3 Major Hurricanes (2 most likely)
Accumulated Cyclone Energy: 75-85 (well below normal)

NOAA 2026 Atlantic Hurricane Season Forecast

More details in Thursday, May 21, 2026 Tropical Update

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Early summer evening with mostly tranquil weather across the Lower 48. A frontal boundary continues to fire storms from Oklahoma into mid-Mississippi River Valley. The main U.S. weather story will be a major heat dome building into July 4th.

While very strong troughing digs into the Pacific Northwest = much cooler air across the Western U.S. for perhaps 2-weeks, a major ridge forms over NE Arctic Canada and extends down an axis into the U.S. Southeast.

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