Big Idea
- A couple of chances for slight precipitation
- Lows in the 30’s, highs in the 50’s
- Weekend sunny but cooler
- Read more...
Tomorrow is Groundhog’s Day
Forecast Summary:
Partly to mostly cloudy with variable mainly high cloudiness and mild temperatures now through Thursday, with perhaps a slight chance for rain showers around the prescott area this afternoon-evening and again Wednesday – Thursday. Accumulations, if any, will be light. Expect gradual snowmelt during this period, as temperatures will be above freezing. Highs in the 50s to near 60. Lows in the 30s. Breezy at times on Wednesday – Thursday, and to a lesser extent on Friday.
For Friday and the coming weekend, expect a transition to mostly sunny and cooler weather, with highs in the low to mid 50s, lows in the upper 20s.
Forecast Table:
https://www.wrh.noaa.gov/forecast/wxtables/
Navigate on the map to your location and click for a detailed local forecast.
Discussion:
Last week, we saw some historic snowfall, which I will affectionately call “Snowpocalypse ‘21”! Most parts of Prescott experienced more snow from Snowpocalypse ‘21 than Snowmaggeddon (Feb. ’19), although some friends from Prescott Valley have indicated to me that Snowmaggedon ’19 was the more significant event. Both of these events rival the Feb. 1987 snowfall that also produced up to 3’ of snow in some places. However, none of them trump December 1967 when two back-to-back storms dumped up to 5’ of the fluffy white stuff over Prescott in one week.
During our recent Snowpocalypse anywhere from 8” to 36” of snow fell around the Prescott area from two back-to-back storms between the evening of Saturday 1/23 until Tuesday evening 1/26. What’s more, with the main cold frontal passage on Monday 1/25, the snowfall became heavy and combined with strong wind gusts well over 40 mph and blowing snow, dropping visibilities to zero. The wind created drifts, with some places experiencing up to 5-foot piles of snow on the south side of town. Unfortunately, Snowpocalypse ’21 did not qualify as a blizzard because blizzards by definition have sustained winds of 35 mph or more for at least three hours with heavy falling snow or blowing snow. We did, however, experience brief periods of blizzard conditions during the passage of the cold front. It was also difficult to measure just how much snow fell, due to the drifts and partial melting and compaction of the snow each day as the snow kept coming down. At my home in Williamson Valley, I measured a total of 27” of snow accumulation, with a maximum of 20” on the ground last Tuesday and over 3’ drifts. The total liquid water for the month of January ended up being about 3.5” at my home and 1.93” at the Prescott airport (which is the official reading). The rain and snow brought welcome drought relief to the Prescott area, after the hottest, driest summer on record and an unusually dry autumn.
Snow is great for the soil and for the flora and fauna of the area. As it falls, it picks up a small amount of nutrients in the air and drops them to the ground. It also allows moisture to slowly soak into the soil, waters trees and shrubs most effectively, and helps replenish our groundwater supply by reducing runoff. At night, the snow and standing water freezes and expands, breaking up the soil and allowing it to become less compacted, aerating it with nitrogen gas from the air (which is also a nutrient when it becomes fixated into the soil). Snow also reflects much of the sunlight, slowing evaporation, and keeping the soil moist for an extended period of time. Nevertheless, Arizona is still under extreme to exceptional drought conditions according to the U.S. Drought Monitor https://droughtmonitor.unl.edu/.
What is the prediction for the remainder of the winter? Tomorrow is Groundhog Day, and as legend has it, if Punxsutawney Phil sees his shadow in Pennsylvania, we’ll be experiencing 6 more weeks of winter. I can assure you, however, that whether or not he sees his shadow, it is certain that there will be nearly 7 more weeks of winter until the vernal equinox, which takes place on Saturday, 20 March.
Don’t forget that we are still experiencing La Niña conditions in the eastern tropical Pacific ocean, which imply a greater likelihood than not of drier and warmer-than-normal conditions for the remainder of the winter and into the spring months (https://www.cpc.ncep.noaa.gov/). The La Niña conditions are expected to weaken to ENSO neutral conditions by the coming spring, but until then we should still expect drier-than-normal to be the more likely outcome.
In the near term, the weather forecast models indicate very little additional precipitation this week. A trough approaching the West Coast is directing considerable high cloudiness across the state and will bring mild southwesterly flow across the state for the next few days before it lifts northward over the Great Basin and skirts around Arizona. The lifting over Arizona with this next system will be minimal, and a portion of the trough is expected to cut off into a closed low and stall over the Pacific Ocean through the coming weekend. Only a slight possibility light showers is expected this afternoon-evening and again Wednesday – Thursday. It will also be breezy at times on Wednesday – Thursday, and to a less extent on Friday. Temperatures will remain above freezing, so the snow will continue to melt slowly these next few days.
By Friday, a weak cold front behind the trough will dive down across Arizona from the northwest, drying the atmosphere out and leading to mostly sunny and slightly cooler conditions for the coming weekend.
C. James
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Curtis N. James, Ph.D.
Professor of Meteorology
Applied Aviation Sciences
Prescott Campus
Met Mail is an unofficial weather discussion and forecast transmitted once or twice a week via e-mail by the Embry-Riddle Department of Meteorology (http://meteo.pr.erau.edu/). Embry-Riddle offers an undergraduate bachelor-of-science degree program in Applied Meteorology. Please spread the word to all potential qualified candidates!
Further Information:
ERAU Applied Meteorology degree program
Official National Weather Service forecast
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