{ "number": 962, "headline": "June 17, 2026 Wednesday Late Spring Weather", "standfirst": "Remnants of Tropical Storm Arthur will drench the Deep South into Friday", "desk": "tropics", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2026-06-18", "published": "2026-06-18T01:46:19.432000Z", "updated": null, "access": "free", "body_html": "
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This is post number 962: Day 169 of 2026. Day 17 of Atlantic Hurricane Season. Good Evening! 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)

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Tropical Storm Arthur was named at 11 AM ET on Wednesday, briefly intensified to 40-knots, and now has moved inland again around Galveston, Texas.

The system is highly wind sheared so quite asymmetric and disorganized. However, Arthur is generating deep convection with embedded gusty winds > 40-knots over the open waters of the Gulf of America. All of that moisture will move inland ahead of the storm into Louisiana and then merge with a stationary frontal boundary.

\u2014> Tropical moisture plume + Arthur + frontal boundary & upper-level jet \u2014> quite a significant rainfall event for several states:

NWS Precipitation Next 72-hours \u2014> Saturday Evening

We could see localized amounts of over 8\u201d in Mississippi \u2026 and 4\u201d-6\u201d into Alabama over the next 48 to 72-hours

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2\u201d around Atlanta, 3\u201d in Macon

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NHC moved Arthur inland \u2014 and will write it off by early Thursday as a post-tropical system

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Arthur\u2019s Second Act?

I think the remnants of Tropical Storm Arthur will maintain coherence and identity throughout its overland trip through the Southeast -- maybe even intensifying with assistance from jet stream. A second act is possible this weekend off the North Carolina coast --> out to sea.

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

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Post-tropical Arthur will look very healthy tomorrow morning swirling into Louisiana and Mississippi

Weather Into Thursday Morning \u2014 Severe Weather Outbreak Continues

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HRRR Forecast Radar into Thursday Noon ET

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Current Convective Situation \u2014 Severe Thunderstorms Within Moderate Risk

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Numerous severe thunderstorms remain likely this afternoon into tonight, with the peak threat centered over Illinois and Indiana. Intense tornadoes, swaths of damaging gusts over 75 mph and damaging wind-driven large hail will all be possible.

Radar Observed to 9:04 PM ET \u2014 please use NWS/favorite app for updates

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

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Weather on Thursday \u2014 strong storm system moves into Quebec (980s mb low pressure) + remnants of Arthur combine with frontal boundary

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

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Boatloads of Rainfall still on the way

Blend of Models \u2014> Precipitation Next 9-days

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Much of the Eastern U.S. will see 2\u201d-4\u201d+ of rainfall \u2014 into last week of June

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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On the periphery of the trough across Canada, storm systems track through the Great Lakes and collect the tropical moisture coming out of the Gulf of America into the warm sector conveyor belt to fuel thunderstorms.

The deep layer moisture plume from the Caribbean into the Gulf of America is shut down into later next week as a ridge forms over Florida and drifts westward to Texas \u2014> subtle pattern shift, but signs it will return flow into the U.S. again

ECMWF 18z | Precipitable Water | My Favorite Parameter

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The main source of high precipitable water air is the Gulf of America, and surges northward into storm systems tracking through the Midwest and Great Lakes.

Temperature Analysis | RTMA | 8:00 PM ET

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Temperature Anomaly | RTMA | 8:00 PM ET

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Lower 48 was +0.9\u00b0F above normal

High Temperatures Next 8-Days \u2014> Friday June 26th

Trying a video upload option rather than GIF \u2014 to see how they play in the app, and how much control there is to the user + email integration.

Low Temperatures on Thursday

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Nice and cool across the Northern Rockies and Midwest

High Temperatures on Thursday

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118 million Americans at least 90\u00b0F \u2014 Texas, Carolinas, Florida, D.C. to NYC add up a lot of population into a smaller area

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Maybe 110\u00b0F in West Central Texas

High Temperatures on Friday

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77 million at least 90\u00b0F \u2026 lost them in the Southeast with the rain & clouds from Arthur

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

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The persistent trough over Ontario and the Great Lakes eventually breaks down and progresses in the Atlantic. However, multiple short-waves spin out of Alaska/Western Canada with the storm track. This limits \u201cheat dome\u201d ridge formation over the Eastern U.S. almost completely through end of June with most abnormal heat confined to the Western U.S.

European Heat Dome Next 10-days centered upon France

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100\u00b0F in Paris on Monday?

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How about 97\u00b0F in London on Monday?

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ECMWF Flagship Ensemble Mean Temperature Anomaly next 15-days

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Week 1 \u2014> June 17 to June 23

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Week 2 \u2014> June 24 to June 30

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Aside from Arthur, the Atlantic basin is very quiet under control of Saharan Air + Dust Layers

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

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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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Tropical Storm Arthur was named at 11 AM ET on Wednesday, briefly intensified to 40-knots, and now has moved inland again around Galveston, Texas.

The system is highly wind sheared so quite asymmetric and disorganized. However, Arthur is generating deep convection with embedded gusty winds > 40-knots over the open waters of the Gulf of America. All of that moisture will move inland ahead of the storm into Louisiana and then merge with a stationary frontal boundary.

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