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821 FXUS65 KBOU 201156 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 456 AM MST Tue Jan 20 2026 .KEY MESSAGES... - Elevated to critical fire weather conditions across the far northeast plains today, with mild and dry conditions across the region. - Glancing arctic outbreak on Friday, with a slight moderation for the weekend. Light snow also possible. && .UPDATE... Issued at 253 AM MST Tue Jan 20 2026 The Fire Weather Watch for this afternoon has been upgraded to a Red Flag Warning. The Red Flag Warning will be in effect for Logan, Sedgwick, and Phillips Counties from noon to 5PM. This event is more on the marginal side and is not a slam dunk by any means. But RH values are forecast to drop into the 13% to 20% range with winds gusting up to 35mph this afternoon, which given how dry the fuels are, we decided to go with an RFW. Winds this morning and early this afternoon will be breezy in the Front Range and the Foothills as a weak mountain wave sets up. Winds were increased for these areas, with occasional gusts up to 70mph in the mountains, up to 60mph in the foothills, and up to 45mph pushing into the adjacent plains. Luckily, these areas saw snow yesterday, which helps to limit the fire weather concerns. But even with the added moisture, we will be looking at elevated fire weather conditons this afternoon for the Foothills due to these strong winds and drying conditions. && .DISCUSSION /Through Monday/... Issued at 222 PM MST Mon Jan 19 2026 It`s been a quiet and sunny day for most of our CWA following the overnight snowfall. The exception to that has been across most of Weld county, which is just finally starting to burn off some persistent stratus/fog that developed earlier this morning. We should still see highs reach the 30s across most of the forecast area this afternoon with little else of note. Tonight should be relatively quiet as dry northwesterly flow aloft continues. Ridgetop winds do strengthen a bit overnight and there will be some gusty winds across most of the Front Range. Can`t rule out a couple of gusts of 60-70 mph overnight or sometime Tuesday, but any mountain wave development looks brief/weak. Tomorrow will be warmer as the cold airmass pushes a little east of our CWA. With warming mid-level temperatures and a more pronounced downslope component, temperatures should be quite a bit warmer than today - closer to 50F across most of the plains. The warm/dry/breezy conditions will lead to some fire weather concerns... see the fire weather section below for more details. A weak cold front is then expected to push into the area late Tuesday evening or Tuesday night, which should usher in slightly cooler (near normal) temperatures for Wednesday and Thursday. A much stronger cold front is forecast to arrive sometime between Thursday and Friday, with well below normal highs likely behind it. We`ll likely remain right on the edge of the colder weather as the deep longwave trough settles over the Upper Great Lakes, but highs on Friday look like they`ll struggle to reach 25F or so. A weak shortwave rounding the base of the trough may also bring some light snow to the area, though QPF forecasts leave a lot to be desired. There is more uncertainty as we get into the weekend, as there`s quite a bit of spread across guidance. As a whole, the GEFS is predominantly on the warmer side, the GEPS is cooler, and the ECME has the most intra-ensemble spread. Unsurprisingly the NBM (and our official grids) were somewhere near the middle of this range for both Saturday and Sunday. && .AVIATION /12Z TAFS through 12Z Wednesday/... Issued at 442 AM MST Tue Jan 20 2026 VFR conditions are expected through this TAF package. Winds at KBJC this morning will be intermittently gusty from the west. Winds at KDEN and KAPA will generally stay from the SW/SSW early this morning, before turning W/WNW around 17Z. Winds will increase from the WNW around 19Z at all TAF sites, with gusts around 25kts at KBJC and 19kts at KDEN and KAPA. Winds will weaken and turn more N/NE around 0Z. Winds will veer this evening, turning towards drainage overnight. There is potential for some wind gusts from the NE as the cold front pushes through around 0Z. Right now, confidence is too low to include any mention of gusts this evening in the TAF, but it`s something we`ll be watching. && .FIRE WEATHER... Issued at 222 PM MST Mon Jan 19 2026 Elevated to critical fire weather conditions are expected to develop Tuesday afternoon across the far northeast corner. There is broad support from model guidance, with the GEFS hot dry windy index (HDWI) near the 75-90th percentile. However, there is still a rather large amount of uncertainty regarding how much wind will be able to mix down during the afternoon... and similarly how low RH will drop. The HRRR remains on the bullish side for both factors, with mixed signals across most of the other reliable short range guidance. Confidence of seeing Red Flag conditions was just a little more than 50/50... and so we`ve opted for a watch for Logan/Sedgwick/Phillips counties, northeast of the band of snow that fell earlier today. Across the Denver metro and South Park, we`ll certainly see dry enough conditions yet again Tuesday afternoon. Most of the I-25 corridor saw enough snow to at least briefly limit the overall fire danger, and winds aren`t quite forecast to reach criteria there. Most of South Park also has less receptive fuels and so we`ve held off on a watch for there as well. && .BOU WATCHES/WARNINGS/ADVISORIES... Red Flag Warning from noon today to 5 PM MST this afternoon for COZ248-250-251. && $$ UPDATE...AP DISCUSSION...Hiris AVIATION...AP FIRE WEATHER...Hiris