Dry weather returns with cool fronts Thursday and early next week
Monday, July 4, 2016
Though we will still be susceptible to afternoon and early evening storms for Independence Day and Tuesday, the atmosphere will continue to dry and warm over the next few days, though at a slightly slower rate than in last Friday’s forecast.
After a mostly dry Wednesday, a wave traveling along the Canadian border midweek will bring the possibility of showers, likely staying to our north for Wednesday night. But cool air will wash over the area on Thursday along with breezy to windy west winds in a still dry atmosphere.
Temperatures should soar to above normal with diminishing winds by later Friday and heading into the weekend as a transient ridge builds behind the departing storm to our north and ahead of another strong Pacific Northwest storm making landfall early next weekend.
By late Sunday or early next week, cooler temperatures, again with breezy to windy westerly winds with still dry weather are expected as that Pacific Northwest storm moves across the northern Great Basin.
Wet weather gradually dries through the long weekend
Friday, July 1, 2016
A wave moving across the well-established monsoon moisture plume currently over Colorado will keep showers going through at least the first half of the night. This wave is strong enough to bring mountain-top northwest flow by tonight which may allow for some drying by early Saturday as the deepest moisture is pushed south behind the departing wave. However, Saturday afternoon storms, possibly strong, will be likely in the still moist and unstable airmass.
By Sunday, moisture erodes further for a drier morning courtesy of a Pacific Northwest storm approaching the coast. But another wave is kicked across Colorado Sunday afternoon by the Pacific storm, and this will again lead to the chance of afternoon storms, possibly strong.
Even though moisture erodes further for Monday, yet another weak wave is forced eastward across Colorado as the Pacific Northwest storm crosses the coast near the Canadian border, and this will again lead the possibility of afternoon storms, though weaker and less numerous than the weekend.
Much drier air overspreads the area on Tuesday and Wednesday accompanied by seasonal temperatures for a very pleasant couple of days.
By Thursday and into Friday, a tropical wave moving from east to west across the Mexican plateau early in the week will travel over our area in continued southwest flow, similar to how the current monsoon event started this past Wednesday. This may again lead to a couple of wet days, though there is model disagreement as to to the duration and depth of this moisture, with the ECMWF being less aggressive than the GFS. In any case, another Pacific Northwest storm looks to make landfall near the end of the work week and westerly flow will cut off the moisture plume by the weekend as the storm moves inland.
Monsoonal surge from midweek through mid-weekend followed by drying
Monday, June 27, 2016
The current hot and dry conditions will transition to a wetter flow by midweek as this season’s first monsoonal moisture surge encroaches over the Steamboat Springs area.
A wave that had been moving from the east in the tropical flow across central Mexico this past week will be absorbed in the southwest flow on the western periphery of the Great Basin ridge tomorrow. After another hot day on Tuesday, with only a slight chance of afternoon storms that will bring more wind than rain if they do occur, humidity will noticeably increase on Wednesday as that wave to our west crosses Utah.
Afternoon showers will become more likely by Wednesday, with some lingering overnight in the moist environment. A cool front from energy traveling around a branch of the Polar Vortex near Hudson Bay will graze northern Colorado and be the focus of more rainfall for Thursday as it interacts with the still moist atmosphere.
Additional waves from the south will keep humidity high and the chance of afternoon storms around for Friday, Saturday and possibly Sunday. Interestingly, a still strong westerly jet stream moving across the Pacific will move another storm to the Northwest coast by Sunday. While models have this storm staying mostly north of us on Monday, drier air filters into our region as soon as later Sunday.
Furthermore, the strong westerly winds from this storm will bring breezy to windy conditions to our area around the Fourth of July and cut off the flow of monsoon moisture from the south through at least midweek. There may also be a cool front, currently timed for Tuesday, that will knock temperatures back to normal on that day.
Weekend cooling followed by more hot weather
Wednesday, June 22, 2016
A strong summer storm currently spinning in the Gulf of Alaska as of Wednesday afternoon, courtesy of a seasonally strong Polar Vortex still dumping cool air around both US coasts, will nudge the ridge of high pressure over our area eastward, allowing a surge of moisture from the south to be drawn northward along the western periphery of the ridge. We should have more extensive cloud cover and our best chance for wetting rains by Thursday afternoon.
By Friday, the Pacific Northwest storm will have has crossed the coast, and the increased westerly winds will cut off the southern moisture feed into our area, though there will still be a chance of afternoon storms. Models move a relatively strong but dry cool front through the area Saturday morning, bringing dry breezy to windy conditions and cooler temperatures for the weekend, especially for Saturday.
Temperatures will rebound to above normal by Monday and last until midweek as the ridge of high pressure rebuilds over the west as cool air from the persistent Polar Vortex keeps troughs of low pressure over the Gulf of Alaska and the East Coast.
By midweek, yet another strong Pacific Northwest storm will again nudge the western ridge eastward, allowing moisture from the south to once again travel over our area. This moisture feed may be more persistent than the current brief surge we are currently seeing, with longer range models keeping what appears to be the beginnings of our monsoon around for the following week.
Monsoonal flow refers to the seasonal reversal of the winds, and in our case this refers to the influx of moisture as southerly winds pick up moisture originally from the Gulf of Mexico that has moved westward across Mexico and moves it over our area.
Hot weather with some moisture for Thursday and Friday before weekend cooling
Monday, June 20, 2016
The couple of weak waves yesterday and today did little more than keep morning temperatures cool as the strong summer sun quickly modified the airmass. Tuesday should be even warmer than today as the western ridge expands directly over the Rocky Mountains.
Another storm passing well to our north along the Canadian border late Tuesday may shave a few degrees off of Wednesday’s high temperatures as the western ridge flattens, and allows some moisture from the south to move northward across Colorado and produce some afternoon clouds. There may possibly be some high-based and relatively dry mountain storms.
Another stronger storm forecast to be off the Pacific Northwest coast by Thursday will nudge the ridge eastward, allowing a stronger surge of moisture from the south to be drawn northward along the western periphery of the ridge. We should have more extensive cloud cover and our best chance for afternoon storms by Thursday afternoon.
By Friday, the Pacific Northwest storm will have has crossed the coast, and the increased westerly winds will cut off the southern moisture feed into our area, though there will still be a chance of afternoon storms. Models move a relatively strong but dry cool front through the area Saturday morning, bringing dry breezy conditions and cooler temperatures for the weekend.
