{ "number": 964, "headline": "June 21, 2026 Sunday Summer Weather", "standfirst": "Atlantic tropics in a long slumber until July. A powerful Typhoon well east of Taiwan will turn north in the coming days away from land.", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2026-06-22", "published": "2026-06-22T01:39:24.086000Z", "updated": null, "access": "free", "body_html": "
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This is forecast post number 964: Day 172 of 2026. Day 21 of Atlantic Hurricane Season. Good Evening! Happy 1st Day of Summer!

Welcome to all new and returning subscribers for another Atlantic hurricane season. We\u2019ll also keep track of the daily weather across the Lower 48, and sometimes around the world.

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

Help support this newsletter (nearing post 1,000!) \u2014> June 2026 Coupon

Weather Trader is entirely reader-supported publication (no ads). To receive all new posts and support our work, consider becoming a free or paid subscriber. ALL CONTENT is original (human \u2014 Ryan) and not A.I. although you can chip in a Starbucks each month for more Claude Max (tokens!)

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Severe thunderstorms about to reach the Ohio River in a convective complex. Embedded tornadoes and risk for damaging winds along with heavy rain, of course.

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NWS Precipitation Next 72-hours \u2014> Wednesday Afternoon

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More rainfall for the lower Great Lakes and Northeast w/widespread 1-inch+

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Much more in Oklahoma with a convective storm complex expected to move southward tomorrow.

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

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Into later Monday, the frontal boundary digs southward and pushes the tropical moisture into Southeast. On the backside of the trough, the MCS forms in southern Kansas and crashes southward through Oklahoma.

Weather Into Monday Morning

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HRRR Forecast Radar into Monday Noon ET

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Rain and embedded storms head into the Northeast with the storm system.

We\u2019ll need to wait until later in the day for new storms to fire up for the Mid-Atlantic.

HRRR Rainfall over the next 48-hours painted by the storms

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Oklahoma and Arkansas with heaviest downpours with this 18z HRRR cycle

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

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Weather on Monday \u2014 Frontal Boundary focus for continued storms and heavy rain as tropical moisture encounters digging trough

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ECMWF 18z | Precipitation + MSLP | Next 6-days

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Blend of Models \u2014> Precipitation Next 9-days

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Continued wet pattern for the Central U.S. from OK/AR up into the Midwest while Texas dries out nicely. Sometimes a break from heavy rain is a good thing in early summer!

Help support this newsletter (nearing post 1,000!) \u2014> June 2026 Coupon

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?

ECMWF 18z | Precipitable Water | My Favorite Parameter

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Generally 1.8\u201d (yellow) PWAT with embedded > 2\u201d convective cells = heavy downpours across Central U.S. into the Southeast.

Temperature Analysis | RTMA | 7:30 PM ET

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Very hot in west Texas > 105\u00b0F \u2026 only 30 million population at least 90\u00b0F at 7:30 PM

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Temperature Anomaly | RTMA | 7:30 PM ET

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Lower 48 was -1.5\u00b0F below normal with clouds and rainfall cooling down the Dakotas, Midwest into the Great Lakes

High Temperatures Next 8-Days \u2014> Tuesday June 30th

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Trend to hotter temperatures across the board into final days of June with 100s building across all of Texas with the much dryer conditions. Southeast including Atlanta and Carolinas push well into the 90s.

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.

210 million+ at least 90\u00b0F by June 30th with Lower 48 average high of 86.7\u00b0F

Low Temperatures on Monday

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40s and 50s from northern Rockies into the Midwest, Great Lakes, and Northeast.

No sign of muggy, heat wave conditions \u2014 windows open!

High Temperatures on Monday

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Up to 120 million at least 90\u00b0F and 14 million at least 100\u00b0F

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

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Strong troughing digs into the Pacific Northwest in the medium range = much cooler across the Western U.S. with potential for mountain snow into early July.

Ridging builds across the Eastern U.S. \u2014> dry and heating up especially across the Southeast

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

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594 dm \u2014> 597 dm (or higher) contours pop up across the U.S. border in AZ/NM and then in the Southeast \u2026 trending warmer \u2014> maybe a more typical \u201cheat dome\u201d centered over the Southeast into early July.

European Heat Dome Next 10-days centered Western Europe \u2014 moves eastward into Germany and Poland \u2026 and potential for another event in 10-days west of the U.K. which could push over Isles.

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104\u00b0F in Berlin maximum next weekend!

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HOT with 99\u00b0F in Paris maximum Wed/Thursday

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96\u00b0F in London on Tuesday and 98\u00b0F to 99\u00b0F on Wed/Thurs

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Temperature Anomaly next 12-days

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ECMWF Flagship Ensemble Mean Temperature Anomaly next 15-days

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Week 1 \u2014> June 21 to June 27

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Cool 7-days ahead for Midwest and Great Lakes \u2014 no complaints

Week 2 \u2014> June 28 to July 4

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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

Atlantic Basin \u2014 Very Quiet through end of June 2026

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Dust Forecast | NASA GEOS-5 Model Next 10-days

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Dust plumes are not particularly intense, but they are noticeable. However, the Saharan Air Layers are more important which blast off the African continent \u2014> warm, stable air at low-levels = suppression of convective (storms) and any tropical waves struggle to even generate a shower.

Tropical Waves \u2026 multiple across the 2 basins but nothing active

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SST Temperature Analysis \u2014 still sub-26\u00b0C over half of the MDR east of 50\u00b0W

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And, that area is much cooler than the last 30-years climatology. Northwest Atlantic is also very chilly

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Satellite Imagery \u2014 not much active convection across the entire Atlantic tropics

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Ensemble Storm Tracks Next 15-days \u2014> Complete Ghost Town in Atlantic

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Global SST Anomaly show the ongoing / intensifying El Ni\u00f1o

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Couple Tropical Waves in Eastern Pacific with Low Chance (20%) in coming week

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Western Pacific Typhoon Season

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Typhoon MEKKHALA has nicely cleared out a large eye

The NW quadrant of the eyewall is not quite complete, but we\u2019re likely looking at a Category 4 Typhoon (115-knots) \u2014 morning out there.

HAFS-A 18z suggests minimum pressure into the 935 mb range \u2014> Super Typhoon at Category 4 \u2014 130-knots.

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Tracks from Full Physics EPS Ensembles + Deep Mind both show a WNW track for next 2-days before recurving to the NORTH and then NNE along/near coast of Japan by weekend.

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JTWC forecast track through 5-days \u2014 max 120-knots winds (Cat 4)

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Full Physics ECMWF Ensembles | Next 15-days

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94W may briefly become a tropical storm \u2026 but watching potential for a long-duration, major typhoon coming across the Dateline into July = a lot of ACE

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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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Severe thunderstorms about to reach the Ohio River in a convective complex. Embedded tornadoes and risk for damaging winds along with heavy rain, of course.

More rainfall for the lower Great Lakes and Northeast w/widespread 1-inch+

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