Thursday, August 15, 2019
The beautiful average summer weather the Steamboat Springs area has been experiencing this past week will continue for the upcoming week. Thanks to a storm traveling across the Canadian Plains, the jet stream is forecast to sag over the northern states this weekend,, bringing a weak cool front through northern Colorado on Saturday. Afternoons and evenings will be breezy to windy for several days around the front as the stouter winds aloft are mixed down to the surface, though they should diminish after the weekend as the jet stream retreats back north and allows a ridge of high pressure to rebound over the West.
High temperatures are expected to be near our average 81 F or slightly above, except a bit cooler for Saturday, while low temperatures are expected near our average of 44 F, except for Sunday morning when they may be cooler, perhaps touching the upper thirties.
It appears the front will bring in enough moisture for some clouds on Saturday, with a small chance of an afternoon or evening shower. Otherwise breezy to windy conditions are expected from this Thursday afternoon through the weekend before a ridge of high pressure rebuilds over the West behind the eastward-moving Canadian storm.
And when a ridge is present over the West in July and August, monsoonal moisture from the south can be transported northward along the western periphery of the ridge. This looks to happen as a weak surge of monsoonal moisture is forecast to start as soon as Tuesday afternoon and continue through at least most of the work week. At this time, it is not clear if the surge contains enough moisture for more than some clouds and a slight chance of showers.
More inconsistency appears in how weather forecast models deal with incoming Pacific energy for the end of the work week. The European ECMWF favors a more progressive and less amplified jet stream than the American GFS, which would keep a drier westerly flow over the central and southern Rockies as we head into the following weekend.
Sunday, August 11, 2019
After a good chance of showers this mostly cloudy Sunday afternoon and evening, much drier air overspreads the Steamboat Springs area starting Monday. Warm and dry weather will dominate the upcoming work week before a Pacific Northwest storm eventually passing to our north introduces breezy conditions heading into the weekend.
A storm currently over Idaho will move across Montana tonight and North Dakota tomorrow, swinging our winds from the south to the west. While the current southerly flow ahead of the storm is supporting the good chance of showers this afternoon and evening, with some storms producing locally moderate to heavy rains at times, the westerly flow behind the storm effectively severs the monsoonal moisture tap that has been with us this weekend and brings much drier air overhead.
So high temperatures around or slightly above our 81 F average with mostly sunny skies are expected for the work week. Around Friday, another seasonably strong strong storm crosses the Pacific Northwest coast, bringing breezy to windy southwesterly winds starting as soon as Friday and lasting through some or all of the weekend.
Weather forecast models disagree on the how strong the storm becomes along the West Coast and how quickly it moves across the northern U.S. as it is dependent upon the strength and location of a ridge of high pressure forecast in the proximity of the Gulf of Alaska. The European ECMWF has a stronger and deeper storm that moves mostly north of our area through the weekend in pieces, while the weaker and faster American GFS moves the storm bodily north of us early in the weekend. More details will emerge by my next weather narrative on Thursday, with the forecast varying between cool, dry and breezy according to the ECMWF to warmer with a chance of showers according to the GFS.
Thursday, August 8, 2019
A shower passed through the Steamboat Springs area early this Thursday afternoon, and another takes aim for later this afternoon. After a downturn in precipitation potential on Friday, shower chances increase again for Saturday, and possibly Sunday before drier air brings warm and sunny weather through most of the work week.
The North American Monsoon rolls on today as moisture is forced northward along the western periphery of a ridge of high pressure over the West. Showers will mostly end by this evening, though there may be a quick early morning shower to our north on Friday caused by a hard-to-discern subtropical wave that may or may not pass by.
But we should see more sun and warmer temperatures on Friday as the monsoonal moisture plume bends to the east for the day, thanks to some energy ejecting out of a storm off the Pacific Northwest coast and briefly turning our light winds westerly.
The Pacific Northwest storm will first slide south before turning east and making landfall near the California - Oregon border on Saturday. The southerly flow ahead of the storm will conspire with the ridge of high pressure to once again draw moisture over our area on Saturday. More hard-to-discern subtropical waves embedded in the southerly flow will increase the chance of showers for Saturday and Saturday evening, though the timing and position of these showers are difficult to predict at this time.
Meanwhile, a battle between the cool fall air mass from the north and the hot summer air mass from the south is fought over the northwestern quarter of the country, and summer wins as the Pacific Northwest storm to our northwest stays to our northwest. Though drier air is advertised for Sunday as the westerly flow associated with the Pacific Northwest storm re-bends the monsoonal moisture plume to the east, there is a chance of strong storms forming during the day.
There is another subtropical wave forecast for later Sunday, though weather forecast models are struggling with the track and timing. We could see good rainfall, or none at all depending on its eventual proximity.
Behind this nebulous subtropical wave, westerly flow brings much drier air first to northern Colorado on Monday and the rest of Colorado by midweek. Chances for precipitation for our area will be close to non-existent through midweek before another Pacific Northwest storm turns our winds back to the south, possibly allowing another round of monsoonal moisture to move northward. If this occurs, look for increasing shower chances as early as Thursday afternoon that extend into the following weekend.
Sunday, August 4, 2019
Seasonably warm temperatures and mostly sunny skies are gracing the Steamboat Springs area this Sunday morning. We’ll see our best chances for wetting rains later today through tonight and again on Wednesday and Thursday as weather disturbances move near our area.
Much of the west is currently underneath a relatively moist ridge of high pressure that has slowly dried over the past few days. An indistinct weather disturbance rounding the ridge of high pressure will increase shower chances later today and tonight as the winds shift from the southwest to the northwest.
There is still a chance of afternoon and evening storms on Monday in the favorable northwest flow behind the weather disturbance, though the atmosphere will dry on Tuesday for the driest day of the work week.
Shower chances will increase Wednesday, and be even better on Thursday, as a stronger disturbance moves northward along the western periphery of the ridge of high pressure over the west and brings another monsoonal surge of moisture overhead.
Meanwhile, a series of storms spinning in the Gulf of Alaska will begin to move eastward late in the work week while flattening the ridge of high pressure over the west. This effectively bends the monsoonal moisture plume eastward and allows drier air to move overhead starting on Friday and continuing through the weekend. Additionally, winds may become breezy from the west over the weekend as the Gulf of Alaska disturbance move across the Pacific Northwest and eventually drags a weak cool front through our area early in the following work week.
Thursday, August 1, 2019
A cool and cloudy Thursday in Steamboat Springs is the result of monsoonal moisture from the south moving overhead. We’ll see a good chance of showers today before conditions dry heading into and lasting most of the weekend. By later Sunday, another push of monsoonal moisture will increase precipitation chances for Monday, and though moisture will decrease for the rest of work week, enough will hang around for the usual chance of afternoon and early evening storms.
Most of the U.S. is currently dominated by an expansive ridge of high pressure centered over the Rocky Mountains. A subtropical disturbance that is currently traveling through the ridge has brought plenty of moisture but cool temperatures to our area, with the 64 F noontime temperature running over 10 F below typical for this time of day.
There is no strong lifting from the subtropical disturbance, so the cool temperatures from the thick cloud cover has inhibited surface heating enough to reduce, but not eliminate, the chance of showers for today and tonight. In fact, thinning cloud cover to our southwest has allowed a line of storms to form in the southwestern corner of the state, and these may be headed toward our area later this afternoon or evening.
As the subtropical disturbance moves east of our area on Friday, temperatures will warm to near our average of 82 F, with further warming and drying expected for Saturday as the ridge of high pressure amplifies over the west.
Concurrently, a series of disturbances drops toward the Gulf of Alaska from the north and split, with some of the energy staying offshore around the Pacific Northwest coast and some racing across the Canadian Plains later in the weekend. Meanwhile, another subtropical disturbance is advertised to move north along the western periphery of the ridge of high pressure over the west even as this ridge is flattened by the disturbance moving across Canada, so look for increasing clouds later Sunday, with precipitation chances increasing again for Sunday night and Monday as this disturbance moves near our area.
The ridge over the west stays put during the work week as it is anchored between the disturbances off the Pacific Northwest coast and the developing Canadian Plains disturbance that is forecast to turn into a strong storm just north of the Great Lakes by the end of the work week. Even though our area will warm and dry for the rest of the work week, enough moisture will remain under the ridge for the typical chance of afternoon and evening storms.
By the following weekend, weather forecast models have the the Pacific Northwest disturbance moving eastward along the southern Canadian border, which significantly flattens the ridge of high pressure over the west. Dry air is advertised to our north, but monsoonal moisture remains to our south, leading to an uncertain forecast for that weekend.