So, April begins, and it looks as though the poet was right. After a brilliant start, with sunshine and temperatures in the 70s, we're looking for cruel lows in the 20s by week's end, with the threat of snow showers in the mountains.
Such excursions into the 20s aren't unusual in April. The record lows for the month range from 15 degrees on April 1, 1923, to 35 degrees on the 27th back in 2001. Snow is quite possible in April. While the average total snowfall in April is just a tenth of an inch, an April Fools storm in 1924 dumped 9.4 inches on the city. Only two other dates have seen more than an inch of snow - on the 10th and 11th in 1894. Only seven dates in April have seen no snow since record-keeping began.
Hot weather is also quite possible, on any April date. The record highs range from 83 degrees early in the month, to 94 degrees, reached on four separate days later in April.
The norms, however, are far milder. The normal afternoon highs rise through the 60s as April progresses, from 60 on the 1st to 69 degrees by the 30th.
The normal overnight lows start out at 38 degrees, and rise to 47 degrees by month's end at BWI.
March ended Saturday night having delivered a surplus of moisture - 4.17 inches. That's a quarter-inch above the long-term averages. The airport set a new record for precipitation on the 16th, with 2.14 inches. That snapped the old record of 1.14 inches, set on that date in 1876.
We had 1.4 inches of snow, on the 7th and the 16th. You can watch the snow retreat northward across the continent during March in this loop generated from satellite snow-cover data.
Temperatures in March averaged 45.1 degrees. That was 1.4 degrees above the norm at BWI. We set a new record high for a March 14, when the mercury reached 83 degrees. That broke the old record of 81 degrees, set on that date in 1990. The low for the month was 14 degrees, on the 8th. That gave the month a temperature spread of 69 degrees.
Here's the month's summary from the NWS folks at Sterling:
"MARCH TURNED OUT TO BE A ROLLER COASTER RIDE AT BWI.
TEMPERATURES REACHED 70 DEGREES SEVEN TIMES DURING
THE MONTH...HELPING TO MAKE MARCH THE 45TH WARMEST ON RECORD.
HOWEVER...ON THE FLIP SIDE THERE WERE SOME VERY COLD AND SNOWY TIMES
AS WELL. FOR EXAMPLE... 0.8 INCHES OF SNOW FELL ON THE 7TH AND
THIS WAS FOLLOWED BY RECORD COLD ON THE MORNING OF THE 8TH."
They're wrong about that last item. The low of 14 degrees on the 8th was not a record. The record for that date in Baltimore is 10 degrees, set in 1960. Nobody's perfect.
Here is your guide to the night sky in April, from the Hubble Space Telescope Science Institute. And here's a link to this year's Stargazer's Calendar. Enjoy.