Warmer temperatures are in the forecast today with a chance of rain. We talk potential snow amounts for the storm headed our way this weekend, and touch on Hurricane Michael.
Remember, these daily forecasts are Premium content. Periodically, we open this forecast up to all of our readers. Today is one of those days!
Sign up today to get the best BoulderCAST experience, including these daily forecasts every morning, complete 6-day skiing and hiking forecasts, additional storm updates and much more!
Don’t forget, TODAY is the last day to take advantage of our 2018 pre-winter promotion. Save 30% on BoulderCAST Premium with promo code SNOW.
Temperature is relative, mind you
Would you believe me if I told you warm southwesterly flow is headed our way today? Really…it is! The 500 mb vorticity map below shows that the trough across the West is elongating currently. By tonight, the portion across California will split away to become a cut-off low. This isn’t a concern for us, though.
Today’s weather focus is the resulting southwesterly flow taking shape across Colorado. The warm air we speak of isn’t actually all that warm, especially considering the cloud cover that will be in place all day today. It will, though, feel nice compared to the snow and 30’s of yesterday. Expect highs to reach into the upper 40’s this afternoon.
GFS 500 mb vorticity map for today. Southwest flow is present across Colorado underneath an elongating trough.
The bad news is that there will also be a slight chance of lower elevation rain and higher elevation snow today. Notice the thin band of precipitation indicated by the GFS across western Colorado and southern Utah (see below on left). If that looks like a jet-forced band, you would be partially correct. Given the 500 mb set-up, this narrow area is also a region of strong diffluence aloft. Air spreading out high in the atmosphere is also a great mechanism for lift! But yes, this area is also in the left exit region of a subtropical, moisture-laden jet streak in New Mexico (see below on right).
GFS precipitation forecast (left) and 250 mb winds (right) for today. In the left exit of the jet, a narrow but intense band of rain/snow is expected across western Colorado.
Almost all of the models show the precipitation remaining entirely south and west of Denver across the Mountains, with that southwest flow downsloping into the Metro area causing only a slight chance of any precipitation actually reaching the ground for us. Nevertheless, from early this morning through this evening, there will be a small chance of seeing light snow in the Foothills and a few sprinkles on the Plains, not amounting to much of anything east of the Divide. Across western Colorado, mountain snow is expected to total in the 5 to 10″ range within that swath.
PowderCAST showing good snow today for many resorts. Not so much for Wolf Creek, though, which has a few lifts opening this weekend!
Snow potential this weekend
It has been a busy weather week. Boulder had its first snow of the year yesterday…reporting around 1.0 to 1.5 inches of snow officially. Hooray! Our next chance of accumulating snow comes Saturday night into early Sunday as a quick-moving trough carves its way into Colorado from Canada. This looks to be our first real “snowstorm” of the season. Several inches are LIKELY for the Metro area. Given the set-up, upslope favored areas in and near the base of the Foothills will be the winners. Temperatures will be plenty cold enough for snow, too. We’re liking the 3 to 6″ range for now, but that could change. Model agreement is good currently, so we don’t expect too much wavering, however.
Category Four
It doesn’t seem like we should be talking hurricanes in the same post as snow, but alas, October is still very much hurricane season. In fact, Hurricane Michael formed in the very same spot that climatology said he should, in the far western Caribbean.
Climatological formation zone and tracks of October tropical cyclones in the Atlantic. Source: NOAA
Incredibly, Hurricane Michael strengthened from a small tropical wave into a Category 4 monster hurricane in just a few shorts days. It’s amazing what the warm waters of the Gulf can do with next to no shear present in the atmosphere. Michael made landfall at his peak intensity with 150 mph sustained winds late Wednesday morning. No doubt, the impacts from Michael will be felt for many months to come along the Florida coastline.
Composite radar image of Category 4 Hurricane Michael just after landfall on Wednesday.
The power of a storm like Michael is almost incomprehensible to most of us. Yesterday’s landfall reminded me of the infamously bleak forecast issued by the National Weather Service on the eve of Hurricane Katrina slamming into New Orleans. To this day, 13 years later, this video below from NOAA Weather Radio gives me chills and brings a tear to my eye. Can you imagine being in the path of Katrina, as someone whom didn’t follow mandatory evacuation orders, huddled in your home, listening to this message?
