Residual moisture circulating underneath a ridge of high pressure aloft produced isolated to scattered showers over southwest Colorado. Given the dry lower levels, gusty outflow winds were the primary threat from showers.
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The episode as NWS GJT wrote it up.
Residual moisture circulating underneath a ridge of high pressure aloft produced isolated to scattered showers over southwest Colorado. Given the dry lower levels, gusty outflow winds were the primary threat from showers.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Junction, CO wrote its last area forecast discussion before the first event at May 28, 1:54 PM MST, 1 hour 42 minutes earlier.
Area Forecast Discussion National Weather Service Grand Junction CO 254 PM MDT Thu May 28 2020 .SHORT TERM...(Tonight through Friday night) Issued at 234 PM MDT Thu May 28 2020 Satellite imagery shows scattered to broken cumulus off of the higher terrain but mostly sunny conditions in many lower elevations. Radar returns remain constrained to the higher mountains with a bit of virga spilling over into the lower elevations downwind. An Omega pattern continues over the CONUS today but both lows will begin to move to the northeast and eventually be entrained within the jet this evening. This will allow us to start breaking down the omega and nudge the ridge (currently the axis remains just west of our forecast area) slightly eastward during the short term. Because of this, expect fairly consistent conditions through the short term with a slight increase in temperatures and a slight increase in moisture as the southwest flow continues. One thing to watch for Friday will be the poential for dry thunderstorms in the lower elevations (especially near the Utah/Colorado border). Moisture in the low levels has not quite caught up to what's trickling in at the mid levels. Thus, inverted-V soundings signal the potential for dry thunderstorms in these lower elevations. Temperatures will continue to climb well above normals for this time of year as the ridge axis moves directly over our CWA. High and low temperatures across the board remain about 10 degrees above normal through the short term. .LONG TERM...(Saturday through Thursday) Issued at 234 PM MDT Thu May 28 2020 Saturday morning the center of the low pressure off the California Coast moves onshore as it continues northeast...leaving behind a high amplitude trough. The energy associated with the cutoff low gets absorbed back into the main jet as it nears the Pacific Northwest by Sunday morning. Thus, the highest winds with that system will likely remain to our west...favoring western and northern portions of the Great Basin. However, elevated to critical fire weather conditions could occur on Sunday as the system scrapes by affecting northeastern Utah and northwestern Colorado. As mentioned in the short term, potential for dry thunderstorms in the low elevations will need to be monitored as we move through the weekend. Slight improvement is expected as we move into the new week with moisture finally working down and moistening the lower atmosphere. The main trough remains over the west CONUS coast and begins to cutoff as we move into the coming week. As this occurs, we continue to slowly build up moisture moving in from the southwest which will allow for daily convection favoring the high elevations and slowly working moistening down into the lower levels. This large trough (in addition to the first disturbance that will have moved through) will force the area of high pressure, currently over the four corners, off to the east. Ensembles really diverge starting Wed/Thu as different members struggle with how to progress the large cutoff low. Another low over the Gulf of Alaska wanders southeast toward the Pacific Northwest coast mid- to-late next week and this will play a role as to how the existing west CONUS trough evolves. At any rate, latest model runs show the initial disturbance riding the wave of the second...leading to a shortwave through the southwest flow sometime late next week. Temperatures to start the long term will remain well above (closer to record maximums than) normals. We slowly cool down Monday and again Tuesday as the high pressure fades further east. However, thanks to the continued southwest flow, the forecast area will plateau off just above normal as we head into mid-next-week. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) Issued at 1158 AM MDT Thu May 28 2020 Some cumulus will build over the high terrain this afternoon with some isolated storms possible mainly over the central and southern divide mountains. KASE has the best potential to see VCTS, but otherwise anticipate gusty outflow winds to 30 kts near any storms. Most sites will be generally breezy this afternoon with occasional gusts to 20 kts with VFR dominating the next 24 hours. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && SHORT TERM...SS LONG TERM...SS AVIATION...MDA
Hazardous Weather Outlook National Weather Service Grand Junction CO 454 AM MDT Thu May 28 2020 COZ001>014-017>023-UTZ022>025-027>029-291100- Lower Yampa River Basin-Central Yampa River Basin- Roan and Tavaputs Plateaus-Elkhead and Park Mountains- Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor- Central Colorado River Basin-Grand and Battlement Mesas- Gore and Elk Mountains/Central Mountain Valleys- Central Gunnison and Uncompahgre River Basin- West Elk and Sawatch Mountains-Flat Tops- Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide- Northwest San Juan Mountains-Southwest San Juan Mountains- Paradox Valley/Lower Dolores River- Four Corners/Upper Dolores River-Animas River Basin- San Juan River Basin-Southeast Utah-Eastern Uinta Mountains- Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat- La Sal and Abajo Mountains-Canyonlands/Natural Bridges- 454 AM MDT Thu May 28 2020 This hazardous weather outlook is for eastern Utah and western Colorado. .DAY ONE...Today and Tonight Thunderstorm development will be possible this afternoon across higher terrain in western Colorado. A better coverage of storms are forecast along the southern San Juans and the Continental Divide. Lightning and wind gusts in excess of 30 mph are possible with a few stronger storms. Showers and thunderstorms will diminish quickly after sunset. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Afternoon thunderstorm activity will likely return across higher terrain each afternoon through early next week. Storms look to become more widespread Saturday into Tuesday. Warming temperatures will continue to eat at the snowpack and flows will be increasing. However at this time no flooding is forecast. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed.
The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
A peak wind gust of 59 mph was measured by the automated weather station at the Durango-La Plata County Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2020Every state in 2020This day in weather historyWarnings in Colorado, May 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 885986.