How does cold snap liken to past ones?
The Phoenix area can expect some cold temperatures this week. We’re talking cover your roses and bring your pets indoors.
The forecast for Tuesday and Wednesday calls for high temperatures in the 50s with overnight lows approaching freezing. Those highs will be about 15 degrees below normal. The normal high for Feb. 4 and 5 is 69 degrees, with an average low of 47.
While any high temperature below 70 degrees would be considered worthy of breaking out the long underwear for some folks in the Phoenix area, this week’s weather isn’t likely to set any records.
In fact, it’s not even that unusual. If you’re wondering when was the last time Phoenix saw such a cool snap in February, you’re either brand new to town or have a really short memory. It was 2019.
It snowed here in 2019
Phoenix saw a 122-year-old record for lowest high temperature fall with a high of 47 degrees on Feb. 22, 2019. Traces of snow fell in the northern edges of the Valley, and overnight low temperatures hovered in the 30s.
It would have to get considerably colder than the current forecast to approach the records this week. The record low for Feb. 4 in Phoenix is 27 degrees; the Feb. 5 record is 28.
The record for lowest high temp is 47 degrees for Feb. 4 and 48 degrees for Feb. 5.
This is what winter here is like
A look at National Weather Service records for Phoenix show that since 2000 the city has experienced at least one day with a high temperature of 59 degrees or below in February 11 times.
In 2019 and 2011 the lowest high for the month was in the 40s. On Feb. 2, 2011, the high was 44 degrees in Phoenix and it only warmed up to 49 degrees the next day.
When it comes to overnight lows, the city saw a February low of 39 de
grees or below nine times since 2000.
The average high for the month is 70.7 degrees while the average low is 48.7.
So this week’s temperatures aren’t a big concern to meteorologists.
“It’s winter,” said Isaac Smith, a meteorologist with the National Weather Service in Phoenix. “The temperatures aren’t all that abnormal for this time of the year.”
Recency bias
However, it only takes a look at some of the record highs set in February in recent years to see why people’s perceptions of the current cold snap might be a bit skewed.
In 2016 alone, seven high temperature records were set, with the warmest day being 90 degrees on Feb. 17. Three records were broken in 2014 with highs of 86 degrees
The five coldest days in Phoenix history were all recorded in January.
The record low is 16 degrees on Jan. 7, 1913. That’s followed by 17 degrees on Jan. 6, 1913; 19 degrees on Jan. 7, 1971, and Jan. 8, 1913; and 20 degrees on three dates in January.
On average the city sees about eight days a year with a low temperature below freezing. Records have been kept since 1895. If you look at the current normal period, the average number of days with a low below freezing is one.
So-called normal periods look at statistics from a 30-year period. The current normal period is from 1981-2010. A new set of statistics will be computed at the end of this year.