{ "number": 926, "headline": "April 27, 2026 Monday Spring Weather", "standfirst": "Moderate Risk [4/5] Severe Weather centered on St. Louis with potential of strong tornadoes", "desk": "notebook", "dateline": { "place": "Weather Trader", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2026-04-27", "published": "2026-04-27T13:35:33.069000Z", "updated": null, "access": "free", "body_html": "
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This is post number 926: Good Morning! Day 117 of 2026.

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

Special April 2026 Coupon for new/upgrade Annual Subscribers, or gifts.

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) and not A.I.

This Morning\u2019s Satellite Imagery

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Strong low pressure system centered on the Corn Belt with ongoing severe thunderstorms within the warm sector.

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SPC: Moderate Risk of Severe Weather \u2014 4 out of 5 centered on St. Louis

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Numerous severe thunderstorms are expected from the mid Mississippi/lower Ohio Valleys into the Mid-South through this evening, with a threat for multiple strong to intense tornadoes (EF-3+), widespread severe/damaging wind gusts, and scattered large to very large hail.

Tornado Potential \u2014 15% + CIG2 = chance of strong/intense tornadoes highest over Missouri and Illinois including St. Louis and Decatur, Illinois

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Lower 48 Weather Today | Monday

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WPC Short Range Discussion:

Developing lee-side cyclone centered over southern Kansas is forecast to lift northeastward into the Upper Midwest, while an associated cold front sweeps across the Nation's mid-section.

A plume of very moist and unstable air continues to surge northward ahead of
the front, which will set the stage for several days of severe weather and
heavy rainfall across the Mid to Lower Mississippi Valleys and Mid-South. HRRR precipitable water next 18-hours:

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Current Radar: 8:54 AM ET

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Fewer severe level storms heading into the morning but heavy rain (not needed) across northern Missouri and eastern Iowa.

Radar next 18-hours \u2014> Tuesday early morning 1 AM ET

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HRRR 06z \u2014 Radar Simulation Next 48-hours to Wednesday 2 AM ET

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The initial wave of rain with the cold front fizzles out early Tuesday but thankfully another surge of moisture arrives in the Deep South \u2014> Southeast heading into Wednesday for very welcome rainfall > 1\u201d across most areas.

Below normal temperatures next 10-days+

ECMWF AIFS 06z | 500 mb Height Anomaly Next 10-days

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A cool and unsettled pattern from the northern Rockies into the Great Lakes and Northeast for the next 10-days with significant / persistent troughing connecting to the cooler Canadian Arctic pool of air mainly out of the north (still snow covered ground).

10 day Precipitation Forecast | New Blend of Models v5.0

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Several bouts of rainfall across the Southern U.S. from Texas to Florida \u2014 good news for the next 1-2 weeks as May starts out wet and cool.

ECMWF 06z Precipitation Type + Intensity | Next 6-days

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Today into Tuesday: powerful low pressure system tracks through the Great Lakes into Ontario with severe weather along the cold front

Rest of week: general cyclonic flow over the Great Lakes and Northeast taps into cooler Canadian air mass \u2014 with moisture could be come snowfall in higher elevations of New England into the weekend.

Total next 6-days snowfall: Light amounts overall, but amazing to see \u201cMay snowfall\u201d

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Temperature Anomaly Next 6-days

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Plenty of cool green and even purple (10\u00b0F to 20\u00b0F below normal) with Texas seeing the most abnormally chilly air to begin May.

High Temperatures Monday

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Hot across Texas with 90s (25 million population) with 70s across the Eastern U.S. including NYC and Boston. Comfortable / beautiful day!

94\u00b0F in Dallas \u2014 maybe 100\u00b0F along the Rio Grande

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Low Temperatures Tuesday Morning

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Still well below freezing across the Rockies and upper-Midwest \u2026 population is only 5.6 million but the real estate is 25% of the Lower 48. 30s and 40s in the Northeast

High Temperatures Tuesday

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RTMA Current Temperature Analysis | 8:00 AM ET

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Lower 48 average was 48.0\u00b0F at 8 AM ET

RTMA Current Temperature Anomaly Analysis | 8:00 AM ET

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Lower 48 was only 0.7\u00b0F ABOVE normal

Weather on Tuesday

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Slight risk of severe weather along cold front sagging into the middle and southern Mississippi River Valley

NDFD NWS Total Precipitation Next 72-hours through Thursday Morning

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NWS Snowfall Next 72-hours \u2014 through Thursday Morning

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ECMWF 06z | Forecast 6-days of Precipitable Water (my favorite parameter!)

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Northerly flow behind cold front = dry Canadian air almost to the Gulf coast by this weekend

ECMWF 00z | Moisture Transport (IVT) next 10-days

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Limited southerly flow over next 10-days after today\u2019s storm and cold front exit into Canada = dry and cool start to month of May

Total Precipitation Next 7-days | Blend of Models

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Blend of Models | Total Snowfall Next 7-Days

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Blend of Models Temperatures | Highs through Tuesday, May 5th

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Blend of Models Temperatures | Lows through Tuesday, May 5th

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Snowfall from ECMWF HRES (15-days)

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Temperature Anomaly | Next 15-days | ECMWF EPS 00z Ensemble Mean

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Extended period of \u201cbelow normal\u201d temperatures dips into the Lower 48 east of the Rockies extending back into northwest Canada through first 2-weeks of May. Where\u2019s the heat dome? Nope!

Week #1 | Temperature Anomaly | April 27 - May 3

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Week #2 | Temperature Anomaly | May 4 - May 10

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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)

ACE: 75-85

Maps sourced from weathermodels.com designed and innovated by yours truly! Please subscribe there for real-time access to the newest maps, charts from all of the weather models including ECMWF and AIFS, and NOAA GFS/GEFS. NOAA WPC and SPC for fronts/convective outlooks.

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Strong low pressure system centered on the Corn Belt with ongoing severe thunderstorms within the warm sector.

SPC: Moderate Risk of Severe Weather \u2014 4 out of 5 centered on St. Louis

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