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<\/a><\/p>\nThe heatwave will continue for the first part of this week with more seasonal temperatures expected at the end of the week to welcome Fall. The number of 90F+ days in Denver for 2018 is now at 57 days, which is 4th<\/sup> overall in the 150 year record. The reason for the current heat wave is a persistent trough<\/span> to our west, which is creating a ridging pattern and southwest flow over the state. Dry, warm air is being entrained from the desert southwest and the 500mb high location has been suppressing the better moisture to our south and east. Taking a look at the water vapor imagery below, Event #1 will occur as the trough<\/span> finally makes it way eastward on Wednesday and Thursday. The eastward movement in the ridge axis should help to pull a bit more low-level moisture into the state, though this is not expected to be a full monsoon<\/span> surge. Unfortunately, trends in long-term models indicate the weak monsoon<\/span> season has come to an end. The best chance for some wetting rain this week will be on Wednesday with more limited showers and thunderstorms on Thursday after a more stable<\/span> air mass moves into the area behind a cold front. At this time there is No Apparent flood threat. Expect temperatures on Thursday to return to more seasonal values. After Thursday, the extremely dry air mass in Nevada (see below) will make its way into Colorado for the weekend. This should again nix the chances for rainfall next weekend, though high temperatures are only expected to be 5-10F above normal. This will be a nice break from the record heat and perfect weather for leaf peeping.<\/p>\n As the trough<\/span> begins to move eastward, the jet will sag over the northwest corner of the state on Tuesday. Without any mid-level moisture, as seen the last couple of days, critical fire weather<\/span> is expected with surface winds speeds in the 15-25 mph range over western Colorado. On Wednesday, there should be an increase in moisture with the trough<\/span> passage, so critical fire weather<\/span> will likely get downgraded to enhanced fire weather over the Northwest Slope and Central Mountains. After Event #1, the dry air from Nevada (mentioned above) will move into the state, but with the jet to the north and west, critical fire weather<\/span> is not expected this weekend. By Monday, another trough<\/span> moves into the Pacific Northwest, which may set up the jet over western and north-central Colorado again. If this occurs, this would bring enhanced and\/or critical fire weather<\/span> back to western and north-central Colorado. Please tune into the FTB for the daily fire outlook as details will likely change.<\/p>\n <\/p>\n Quite the drastic GEFS moisture plumes below. Still seeing the diurnal signal over eastern Colorado with strong low-level moisture return on Wednesday. Regrettably, this looks to be short-lived with high, post-frontal Precipitable Water<\/span> (PW<\/span>) values only remaining over southern and southeastern Colorado on Thursday. There will likely be heavy cloud cover on Thursday morning with spotty rainfall, limiting instability for afternoon storms on Thursday. More seasonal PW<\/span> values expected after Thursday, which should produce some afternoon cloud cover and possibly some isolated<\/span>, high-based thunderstorms over the mountains. For western Colorado, PW<\/span> values look to increase on Wednesday across the southern half of the region associated with the trough<\/span> passage. This will bring some high-based thunderstorms to the San Juan Mountains capable of gusty winds and dangerous lightning. Increased cloud cover is more likely over the northern high terrains as well on Wednesday. After Wednesday, the extremely dry air mass drops PW<\/span> values well below normal. This could cause some enhanced and critical fire weather<\/span> through the beginning of next week.<\/p>\n<\/a><\/p>\n