Morning stratus clouds along the mountains – Pic taken 3/14/2023
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Tuesday – 14 Mar 2023 – 10:00am
The past…
At Stevens Field the high temperature yesterday afternoon was 45. The low this morning was 27. Winds yesterday afternoon peaked at 11ph.
| Average High | Record High / Year | Average Low | Record Low / Year |
| 47 | 62 / 1995 | 14 | -21 / 1913 |
Precipitation summary… A few showers popped up yesterday afternoon over the mountains, but no measurable precip was reported in the valley.
Forecast discussion…
Rest of today… An upper level ridge will move through and keep us dry. Tonight clouds and the chance for showers will increase, especially over the mountains. An inch or two of snow is possible in the mountains by sunrise Wednesday.
Temps… Highs will be in the mid-40s to low 50s lows will be in the mid-20s to mid-30s.
Winds… Afternoon winds will peak 10-15mph.
Wednesday through Thursday night… The next system will move through. The storm track, storm energy, and moisture are all lining up for another round of a sloppy wintry mix in the valley and snow in the mountains. The amount of warm air and snow levels are going to be challenging again.
Temps… Wednesday highs will be in the high 30s to mid-40s and lows will be in the high 20s to mid-30s. Thursday highs will be in the high 30s to low 40s and lows will be in the high teens to mid-20s.
Winds… Peaks winds will be in the 15-20mph range.
Snow levels… Will bounce around the 8,000ft to 8,500ft range late Wednesday morning to late Wednesday evening. Coincidentally that’s when the heaviest precip is expected. Then snow levels will gradually lower below 7,000ft by sunrise Thursday.
Timing… The first scattered showers will start over the mountains early Wednesday morning and then over the valley later in the morning. Precip will ramp up during Wednesday afternoon and fall pretty good into Thursday morning. Scattered snowshowers will persist into Thursday night, especially over the mountains.
Precip amounts…
Valley below 7,600ft: 0.50” to 1.00” of liquid equivalent and 1-4” of snow
Valley above 7,600-8,400ft: 0.70” to 1.10” of liquid equivalent and 3-6” of snow
Valley above 8,400ft: 0.75” to 1.25” of liquid equivalent and 4-8” of snow
Mountains above 9,000ft: 15-25” of snow
*** In the valley we’ll get a sloppy mix of rain and heavy wet snow. It will start as snow tomorrow morning, transition to rain/snow during the day, and then switch back to snow Wednesday night. Roads in the valley will get slick Wednesday night and Thursday morning. ***
*** The Pueblo NWS has issued a WINTER STORM WARNING for the eastern San Juan mountains above 10,000ft – this includes Wolf Creek Pass. It’s for 8-24” of snow and winds to 50mph valid midnight tonight to midnight tomorrow. ***
There is also a warning for the southwest San Juan mountains, but it does not specify an elevation. The warning area includes many of us in the Pagosa area above 7,500ft. However, I do not expect most of us to get the snow amounts indicated in that warning due to warm air and snow levels 8,000-8,500ft.
Precip, mostly snow, starts in the early morning over the western part of the county and moves east across the county. Then showers are mostly over the mountains through much of tomorrow morning. By 11am to noon, precip is over most of the county and falls moderately to heavily until around sunset. Note the rain vs snow is pretty high up the valley, possibly to 8,400ft. Tomorrow evening precip becomes more scattered. Finally another band of precip moves through tomorrow night and changes to snow for much of the county. Most of the other forecast models expect scattered showers to persist into Thursday afternoon.
Friday and Saturday… The pattern will remain unsettled but disorganized. There will be less moisture to work with and limited storm energy, but we’ll continue to see scattered showers, especially over the mountains. The chance for snow will ramp up Saturday night.
Temps… Highs will be in the mid-30s to low 40s and lows will be in the high teens to mid-20s.
Winds… Afternoon winds will peak in the 15-20mph range.
Precip forecast…
Valley: 0-2” of snow
Mountains above 9,000ft: 3-6” of snow
A quick look at the 15-day period…
Things are lining up for a significant amount of precip over the next 9-10 days and then we should get a break. Just about every long range forecast model indicates 2” to 3.5” of precip by next Friday, 24 March. To put that in perspective, we average 1.77” of precip for March. We could finish March with at least double our average precip!
Let’s start at the top… The top chart shows 24-hour precip amounts for 50 different versions of the Euro model. A quick look tells me to expect precip every day starting tomorrow morning through next Thursday night and then we should dry out.
The middle chart graphs the mean of the 50 versions and the control. I pay most attention to the mean and like the mean and the control to line up pretty closely. In this case, they don’t line up too well for all three storms. This makes my confidence in the timing and amounts a little shaky.
The bottom chart graphs total precip of the mean and the control. Again I pay most attention to the mean and like to see the control line up with it. In this case they line up pretty well but there are minor differences in timing and amounts. First off, it expects over 3” of precip between tomorrow morning and next Friday morning, 24 March – that’s impressive! System 1 is around 1.25”, system 2 is around 1”, and system 3 is also around 1”.
The big question is “do I buy it?”. Yes, for the first system but I want to see better data for the next two. Right now I’m confident we’ll get over 2” of precip during the 10-day period but am hesitant about 3”. Good forecasters continuously initialize and verify forecast models and I’ll certainly being doing a lot of that during this period!
Stream flow and Navajo Reservoir levels…
Stream flow is just starting to increase. The recent storm brought a good amount of rain and wet snow in the valley. And longer days and warm temps are also melting snow in the valley. The mountains aren’t playing a role in the increased stream flows – their snowpack is still building.
Colder temps and lots of clouds may pause valley run-off for the next 10 days or so, and then it will ramp up again. Mountain run-off might not start for another month! It’s going to be interesting to track our stream flows and lake levels over the next couple of months!
My next forecast post will be tomorrow.
– Shawn
3 Responses
David, we only had .80”. Your automated weather station probably had accumulated snow/ice from previous storms & it melted this week.
Please continue to monitor and report stream flows, particularly the San Juan, well
beyond the end of runoff. Thanks!
How much precip did you get from last weeks storm? My weather station had 2.7″ but that might not be accurate. Thanks.