Shower chances return starting Friday
Thursday, August 12, 2021
Temperatures are around eighty degrees in the Steamboat Springs area under cloudless and less smokey skies this Thursday noon, on their way to the mid and upper eighties. The chance for afternoon and evening showers returns on Friday and at least Saturday as some moisture returns to the area, with our first fall-like cool front forecast to approach our area around midweek
A broad ridge of high pressure currently sitting over the Gulf of Alaska and extending into the Intermountain West is flanked by deep and cold areas of low pressure over the Bering Sea and Hudson Bay. The Bering Sea storm is forecast to move east and force the ridge of high pressure to also move east and weaken over the weekend.
Indistinct circulations under the ridge of high pressure will allow some moisture from the south to move overhead starting on Friday, fueling possible afternoon and evening storms for Friday and Saturday with continued warm afternoon temperatures around five degrees or so above our average of 81 F. The refreshingly cool overnight lows will continue to run around or a few degrees below our average of 45 F.
The Thursday morning NOAA smoke plume forecast has some smoke hanging around today and tomorrow, though far less than we saw earlier in the week when winds from the west transported smoke from California wildfires directly into our area. This model has the smoke increasing modestly on Saturday as winds circulating underneath the ridge of high pressure carry smoke originally from the British Columbia wildfires over the region.
By mid-weekend, the Bering Sea storm is forecast to move into the Gulf of Alaska and by late Sunday cross the Pacific Northwest coast. We may see some dry air ahead of the storm on Sunday for a reduced chance of afternoon storms, or not, under continued above average temperatures.
By Monday we will see another warm day with increased winds from the southwest as the Pacific Northwest storm moves inland, with the storm currently indicated to bring a couple of the season’s first fall-like cool fronts through the region around late Tuesday or Wednesday and Friday. And it looks like there will be significant moisture drawn northward in the southwest flow associated with the Pacific Northwest storm as it moves eastward, so beneficial rainfall of over a quarter inch is likely.
Stay tuned to my next regularly scheduled weather narrative on Sunday afternoon for details on what may be our first cool fronts of the season and the increased chances for wet weather next week.
Warming temperatures this week under continued smokey skies
Sunday, August 8, 2021
After a break from the smoke on Friday, it has returned to the Steamboat Springs area this weekend with temperatures in the upper seventies early this Sunday afternoon under sunny but hazy skies. While smoke should decrease later this afternoon and evening, its back tomorrow as a grazing storm increases winds from the west. We probably won’t see much cooling tomorrow associated with the dry storm, but high temperatures will increase into the mid-eighties on Tuesday and remain there for the rest of the upcoming week, save for possibly Thursday when another grazing wave may briefly knock temperatures down a few degrees.
As it looks like the smoke in our area will not be short-lived, I have installed the Purple Air widget at the top of the SnowAlarm home page, and have added another smoke forecast map at the top of the NOAA smoke plume forecasts page. This forecast map shows improving air quality this afternoon and evening, though another batch of smoke from the California wildfires overspreads our area after midnight and Monday as winds from the west pick up due to a storm to our north grazing our area tomorrow. We may see temperatures knocked back to around our average high of 82 F on Monday if any of the cool air makes it into our region, but if not, expect another warm day.
While the smoke may inhibit the warming during the day, luckily it does not interfere with nighttime cooling, so expect low temperatures around our average of 45 F, or even a bit cooler in low-lying areas and possibly on Tuesday morning as a cooler air mass grazes our area.
Behind the grazing storm on Monday, a ridge of high pressure builds over the Gulf of Alaska through the work week, decreasing winds and shifting them to be from the northwest. The smoke plume model only goes out 48 hours, but similar to Saturday, this wind direction is likely to move smoke from the British Columbia fires over our area, though that is just a guess.
So expect temperatures to stay warm for the work week, with possibly a bit cooler start to the day on Thursday morning as a wave moves over the ridge of high pressure to our west into a low pressure area centered over Hudson Bay and extending southward into the Midwest.
Weather forecast models do have that ridge of high pressure over the Gulf of Alaska moving eastward around the weekend, though disagree on how quickly that happens and the strength of the high pressure system. They do agree that our winds will shift to be more from the south, which should not only clear the air of the work week smoke but introduce some moisture to our area, though it is too early to tell if we will see any precipitation.
There may be a better surge of moisture from the south after next weekend, but that is dependent upon the strength of incoming Pacific storms which are not well represented a week away. So stay tuned to my next regularly scheduled weather narrative on Thursday afternoon for details on next weekend and the following work week, and feel free to regularly consult the SnowAlarm home page for the current air quality status, temperatures and wind.
Smoke briefly clears on Friday ahead of breezy cool front
Thursday, August 5, 2021
Temperatures in the Steamboat Springs area are around eighty degrees under cloudless but smokey skies early this Thursday afternoon. The smoke will briefly clear on Friday ahead of a cool front that should bring breezy winds from the west along with a chance of afternoon showers. A cooler Saturday will be followed by a warmer Sunday before temperatures are knocked back again by several degrees through midweek by a couple more grazing cool fronts.
Our weather has transitioned from a very productive week of monsoonal flow typical of mid to late summer to a drier regime with flow from the northwest more typical of late summer to early fall. The past persistent ridge of high pressure over the West has been vanquished for the medium term by a series of low pressure areas from the Pacific Northwest and Canada that has severed the moisture flow from the south and brought cooler air from the northwest overhead.
But not before we added to the rainfall totals discussed in the Sunday weather narrative, with an additional half inch reported in town and around Steamboat Lake on Tuesday and Wednesday with closer to three quarters of an inch on the mountain and around Stagecoach reservoir.
Interestingly, the temperature range between the high and low on Tuesday was only nine degrees between the low of 56 F and 65 F as clouds inhibited warming during the day and cooling at night, and increased over three times that to thirty degrees on Wednesday as the low fell to 48 F, 2 degrees above average and the high rose 78 F, 4 degrees below average.
Unfortunately, the shift in the weather pattern has also transported smoke from fires in British Columbia into our region, though that is expected to clear on Friday as winds shift to be from the southwest early in the day ahead of a cool front later in the day. There is a bit of moisture associated with the front, so expect increasingly breezy winds from the west as the front approaches, with some passing showers in the afternoon.
Saturday temperatures will be several degrees below average, though the winds from the west will again transport smoke into our area according to the latest NOAA smoke plume model, this time from the northern California wildfires. Temperatures warm to above average on Sunday as a transitory ridge of high pressure builds over the central Rockies ahead of dry grazing cool front on Monday that knocks temperatures back again. Temperatures may try to rise a bit for Tuesday but another dry grazing cool front is currently timed for Wednesday.
A ridge of high pressure is forecast to move into the Gulf of Alaska by midweek and build over the West soon after, so another warm spell with temperatures five to ten degrees above average will follow the near-average temperatures earlier in the week. Weather forecast models disagree on the exact orientation of the ridge of high pressure by next weekend, and we could see the return of modest monsoonal moisture, or not, under continued warm temperatures. As usual, I’ll know more by my next regularly scheduled weather narrative on Sunday afternoon.
Wet Monday and Tuesday followed by warming and drying
Sunday, August 1, 2021
Comfortable temperatures in the mid-seventies and mostly sunny skies are over the Steamboat Springs area early this Sunday afternoon. We’ll see a downturn in rain chances today before they increase substantially for Monday and Tuesday ahead of warmer and drier weather that is forecast to last into next weekend.
As has been the case for much of the summer, a ridge of high pressure over the West is sandwiched between areas of low pressure located over the Gulf of Alaska and the Hudson Bay region. However, the orientation of the ridge since this past Wednesday has allowed moisture associated with the North American Monsoon to infiltrate our area as it travels northward along the backside of the ridge, leading to some rain over our region each day. Additionally, an eddy from a storm off the Northeast coast last weekend has slowly traveled across the Gulf Coast states last week and near our area these last few days, providing increased lift and a focus for storms.
In fact, some of the daily rainfall observations have been impressive, but inconsistent, as some areas received good rainfall one day only to see the best rainfall shift to another area the following day, which is usual during monsoon season. Luckily, the regional totals since last Wednesday are more evenly distributed, with generally around a half inch near town and around twice that in some areas in north and south Routt county.
Rainfall chances will decrease for today, though still be present later this afternoon and through the evening as the ridge of high pressure is nudged westward by a storm currently traveling through the Great Lakes that is associated with that Hudson Bay area of low pressure. This shift temporarily moves the monsoonal moisture plume to our west for the day and results in a decreased chance of showers.
However, rainfall chances increase on Monday, and even more so on Tuesday as that eddy originally from the east mixes with some energy ejecting out of the Gulf of Alaska low pressure area and nudges the ridge of high pressure back to the east. This allows the monsoonal moisture stream to move back overhead, and combined with the forcing from the eddy, could produce periods of moderate to heavy rainfall from Monday afternoon through Tuesday night.
Around Wednesday, energy that had earlier ejected out of a strong storm in the Bering Sea will begin moving pieces of that Gulf of Alaska storm eastward, with the southern part of the storm crossing the northern California coast midweek and the remaining part crossing the Pacific Northwest coast early in the weekend.
The first piece of the storm will nudge the ridge of high pressure to the east and bring dry air overhead, warming temperatures and substantially decreasing rain chances, with storm activity relegated back to its usual afternoon and evening time slot.
Even warmer temperatures closer to and a bit above our average of 82 F are forecast for the rest of the work week and the beginning of the weekend, with only small chances for late-day storms. Incidentally, our average daily temperature, shown in the Local Temperatures, Winds & Precipitation section on the SnowAlarm home page, took its first dip of the season today, indicating that, on average, the hottest part of the summer has passed.
Our weather could get more interesting again as soon as the end of next weekend as the northern piece of the Gulf of Alaska storm moves close enough to encourage moisture-rich flow from the south to move back over our area. The timing and evolution of this pattern will almost certainly change over the coming week, but right now it looks like good chances for precipitation later Sunday and overnight followed by cooler weather with continued shower chances to start the next work week.
I expect to again be reviewing good rainfall totals for the coming couple of days in my next regularly scheduled weather narrative on Thursday afternoon, as well discussing that evolving Gulf of Alaska storm and it’s effect on our late-weekend weather, so be sure to check back for the details.
Good rainfall chances through the weekend
Thursday, July 29, 2021
Temperatures are in the mid-eighties early this Thursday afternoon in the Steamboat Springs area as storm clouds begin to build. After another hot day today with the high temperatures once again approaching ninety degrees, a good chance for some rain appears for this evening. And even better chances for rain last from Friday afternoon through Saturday night, and again Monday as a well-established monsoonal moisture plume bringing moisture from the south remains overhead.
A broad ridge of high pressure currently centered over the eastern Colorado border extends northwestward into British Columbia and is sandwiched by deep areas of low pressure over the Gulf of Alaska and the Northeast. The North American Monsoon is likely peaking as moisture originally from the Gulf of Mexico is carried first westward and then northward in the clockwise flow around the high pressure, which means good chances for precipitation for our area in north-central Colorado.
Those chances start late this afternoon and last through the evening as a subtle upper level disturbance, likely the remnant of an eddy that formed to the south of an area of low pressure off the East Coast last weekend, interacts with the moistening air mass over our area. Rainfall could be moderate to heavy at times under the stronger cells, especially between around 8 pm and midnight tonight.
Even better chances for rainfall emerge starting Friday afternoon with showers possibly lasting through the night, again with some producing moderate to heavy rainfall. These higher chances persist through the day and night Saturday, with the most likely short-lived period for drier weather Saturday morning.
So after a hopefully partly soggy Saturday, Sunday should be drier, though still with a chance for afternoon and evening storms, as a wave travels down the east side of the ridge of high pressure over our area and nudges it to the west, briefly dragging some drier air overhead.
But good rainfall chances return for Monday afternoon and evening as some energy ejects out of the Gulf of Alaska storm and nudges the ridge of high pressure back to the east, bringing the monsoonal moisture plume back overhead.
While the weather forecast models agree that at least some of that Gulf of Alaska storm will eject eastward, the timing is uncertain and that may happen Tuesday or Wednesday. This is important for our weather since the flow of monsoonal moisture will be severed by the winds from the west when that happens, so it is unclear if drier weather appears earlier or later in the work week.
Furthermore, this wave of Pacific energy may indicate the end of this monsoon season for our area as the summertime ridge of high pressure grows weaker as the days grow shorter and cooler. In fact, the American GFS is hinting we may see our first fall-like cool front later next week, though the European ECMWF keeps more of that Gulf of Alaska storm off the coast and the ridge of high pressure over the West bruised, but still intact.
Stay tuned to my next regularly scheduled weather narrative on Sunday afternoon when I hope to to review some of the rainfall totals around our area as well as have a better idea on the fate of the ridge of high pressure over the West.
