Composite Map Day 8-14

Probabilistic Outlooks Temperature Hazards Precipitation Hazards Wind Hazards Snow Hazards

Valid Thursday February 26, 2026 to Wednesday March 04, 2026

US Hazards Outlook
NWS Climate Prediction Center College Park MD
300 PM EST February 18 2026

Synopsis: Strong surface low pressure is favored to persist over the Gulf of Alaska throughout the week-2 period, resulting in prolonged moist onshore flow for the Pacific Northwest and bitterly cold northerly flow for Alaska. A fast-moving surface low pressure system is favored to form over the Plains late in week-1 and may bring heavy precipitation to many parts of the northwestern Contiguous U.S. (CONUS).

Hazards

• Moderate risk of heavy precipitation for portions of the Pacific Northwest, Thu-Sun, Feb 26-Mar 1.
• Moderate risk of heavy precipitation for portions of the Ohio Valley, Thu-Fri, Feb 26-27.
• Slight risk of heavy precipitation for portions of the Pacific Northwest and Northern California, Thu-Mon, Feb 26-Mar 2.
• Slight risk of heavy precipitation for portions of the Ohio, Tennessee, and Middle Mississippi Valleys, Appalachians, and Great Lakes, Thu-Fri, Feb 26-27.
• Moderate risk of heavy snow for portions of the Cascade Mountains, Thu-Mon, Feb 26-Mar 2.
• Moderate risk of heavy snow for portions of the Northern Rockies, Thu-Sat, Feb 26-28.
• Slight risk of heavy snow for the Cascades, Klamath, and Sierra Nevada Mountains, Thu-Mon, Feb 26-Mar 2.
• Slight risk of heavy snow for much of the Northern Rockies, Thu-Mon, Feb 26-Mar 2.
• Slight risk of heavy snow for portions of the Upper Mississippi Valley and Great Lakes, Thu-Fri, Feb 26-27.
• Slight risk of heavy snow for much of New England, Thu-Fri, Feb 26-27.
• Moderate risk of high winds for the Pacific Northwest, Northern Great Basin, Northern and Central Rockies, Thu-Mon, Feb 26-Mar 2.
• Slight risk of high winds for the western CONUS and western portions of the Central and Northern Plains, Thu-Mon, Feb 26-Mar 2.
• Slight risk of high winds for much of the eastern CONUS, Thu-Fri, Feb 26-27.
• Slight risk of high winds for the southern coast of the Alaskan Mainland and Southeastern Alaska, Thu-Wed, Feb 26-Mar 4.
• Moderate risk of hazardous cold for much of southwestern Mainland Alaska, Thu-Wed, Feb 26-Mar 4.
• Slight risk of hazardous cold for all of Alaska, Thu-Wed, Feb 26-Mar 4.

Detailed Summary

For Saturday February 21 - Wednesday February 25: WPC Days 3-7 U.S. Hazards

For Thursday February 26 - Wednesday March 04: At the outset of week-2 multiple model ensembles depict a shortwave trough moving across the Plains and into the Northeast U.S. late in week-1 and into week-2. While most of the impact from this system is now likely prior to the forecast period, model guidance continues to indicate a lingering potential for hazardous weather impacts across the East early in week-2. Uncalibrated probabilities from the ECENS and GEFS both indicate at least a 20% chance of day-8 (Feb 26) precipitation accumulations to exceed 1 inch, and only slightly weaker chances of the same on the following day over much of the Ohio Valley. Uncalibrated probabilities from both models also indicate a broader area where chances of daily precipitation accumulation to exceed half an inch for days 8-9, as well as a 20% chance of 3-day snowfall accumulations to exceed 6 inches for portions of the Upper Mississippi Valley and New England. Tight surface pressure gradients are also depicted by multiple model ensembles over much of the Eastern Seaboard, which are favored to enhance winds across much of the eastern CONUS as this system progresses. Taking all of this into account, the following hazards are issued: a moderate risk of heavy precipitation for much of the Ohio Valley, a slight risk of heavy precipitation for the Ohio, Tennessee, and Middle Mississippi Valleys, Appalachians, and southern Great Lakes regions, a slight risk of heavy snow for portions of the Upper Mississippi Valley and much of New England, and a slight risk of high wind for much of the eastern CONUS as well as portions of the Southern Plains, all valid Feb 26-27.

A persistent strong surface low pressure system is depicted throughout week-2 over the Gulf of Alaska by multiple model ensembles. This feature is favored to provide sustained moist onshore flow into the Pacific Northwest, as well as usher in bitterly cold Arctic air into Alaska. Today’s model solutions are less bullish with regard to the potential for hazardous precipitation and snow along the West Coast, but more bullish with respect to hazardous cold in Alaska. Ensemble mean temperatures from the ECENS and GEFS depict widespread minimum temperatures below -20F throughout week-2 for much of Mainland Alaska and single digits for Southeastern Alaska. Deep surface low pressure over the Gulf of Alaska is favored to enhance winds along the southeastern and southern coasts of the state as well, resulting in even colder wind chills. A moderate risk of hazardous cold is issued for much of the southwestern Mainland of Alaska, a slight risk of hazardous cold is posted for the whole state, and a slight risk of high winds for the southern coast and Southeastern Alaska, all valid for the entire week-2 period.

Further south, this persistent surface low is favored to bring enhanced precipitation to portions of the northwestern CONUS. Today’s model solutions for integrated water vapor transport (IVT) indicate a narrower band of enhanced moisture moving into the West Coast, focused on the Pacific Northwest.The IVT tool from the ECENS and GEFS both show weak signal at 250 kg/m/s but persistent signal at the 150 kg/m/s threshold focused north of Cape Mendocino which weakens towards the end of week-2. The Probabilistic Extremes Tools (PETs) from the ECENS and GEFS also indicate at least a 20% chance of 3-day precipitation accumulations to exceed the 85th climatological percentile through the middle of the forecast period. Uncalibrated probabilities from both models keep the strongest signal north of California, with widespread probabilities over 40% of 3-day precipitation accumulations to exceed 2 inches. A moderate risk of heavy precipitation is posted for portions of the Pacific Northwest for Feb 26-Mar 1, and a slight risk is posted as far south as the San Francisco Bay, valid Feb 26-Mar 2. Localized flash flooding is possible with anticipated heavy precipitation. Rises on rivers and urban flooding is possible, but widespread flooding is not expected at this time.

Further inland, a moderate risk of heavy snow is issued for the Cascades for Feb 26-Mar 2, while a slight risk of heavy snow extends further south to include the Klamath and Sierra Nevada Mountains, also valid Feb 26-Mar 2. However, model solutions indicate less penetration of this moisture into the Interior West, limiting the potential for much needed snowfall over the Rockies. Uncalibrated probabilities from the ECENS in particular still show strong signal for heavy snow over the Northern Rockies early in week-2, with chances for 3-day accumulations of at least 1 foot of snow exceeding 40% in some locations. A moderate risk of heavy snow remains posted for the Bitterroot Mountains for Feb 26-28, while a slight risk of heavy snow extending further south into the Wind Rivers and Tetons is warranted for Feb 26-Mar 2. Finally, tight pressure gradients are depicted across much of the West Coast associated with the low pressure over the Gulf of Alaska. This is likely to result in enhanced winds across much of the West, particularly for the Pacific Northwest, northern Great Basin and along the Continental Divide. Ensemble mean wind speeds from the ECENS and GEFS regularly exceed 20mph across these regions, and above 30mph along the I-80 corridor through the middle of the week. The PETs from the GEFS and ECENS also show strong signal, with 40% chances of 3-day wind speeds to exceed the 85th percentile across much of the West. A moderate risk of high winds is posted for the Pacific Northwest, Northern Great Basin, and Northern and Central Rockies, and a slight risk for the western CONUS as well as western portions of the Great Plains, both valid Feb 26-Mar 2.

Forecaster: Danny Barandiaran

$$ Please consult local NWS Forecast Offices for short range forecasts and region-specific information.

Resources

Week-2 Probabilistic Extremes Tool

GFS Ensemble Forecasts