Irishtown Reservoir, Moncton, 05 Nov 2017 (Dearing)
Autumn has made an abrupt return to Southeast New Brunswick.
The passage of a cold front lowered daytime highs in Greater Moncton from a near record of 19.3 C to a below seasonal high of 5.2 C over the past 24 hours.
Temperatures are poised to drop even lower later this week when the first blast of Arctic air this season moves into the Maritimes.
Environment Canada is forecasting a low of -7 C by early Saturday which will likely mean a hard, killing frost for any remaining sensitive vegetation.
Patchy frost in NE Moncton, 01 Oct 2017 (Dearing)
Perhaps it’s fitting that October has begun with patchy frost in Greater Moncton given that autumn weather arrived abruptly just days ago following a stretch of hot summerlike conditions.
Environment Canada had issued a frost advisory for three nights running (and another one has been issued tonight) for Southeast New Brunswick but frost finally made an appearance early today when the thermometer dropped to -1.0 C.
Fortunately, the flower boxes on my balcony were not affected and I brought my tomato plant inside just in case.
The last time the temperature fell below freezing in Greater Moncton was 06 June which means 116 days were consecutively above freezing in 2017.
Frost covers a maple leaf (Twitter)
Environment Canada issued a frost advisory late Sunday afternoon for Greater Moncton and Southeast New Brunswick – almost a month before the average date of the first fall frost.
Clearing skies and light winds with temperatures falling into the lower single digits could have resulted in scattered frost.
However, the frost advisory ended early this morning when the threat was no longer expected.
The low at the Greater Moncton International Airport was 7.2 C which is several degrees away from any threat of frost.
However, the morning low in Edmundston was a chilly 1.1 C.
Sunset at Parlee Beach, NB, 18 July 2017 (Dearing)
Late July is typically the warmest period of summer in Greater Moncton but a recent cool down has brought September-like days and a record overnight low.
On 23 July, the temperature fell to 6.9 C at the Greater Moncton International Airport which broke a record low of 7.2 C from 1962.
A frost advisory was posted in northwest New Brunswick with a chilly low of 2.4 C in Edmundston.
The short term forecast calls for more seasonal highs in the mid-20’s C and lows near 13 C.
A break in clouds over the Nova Scotia-New Brunswick border, 03 June 2017 (Dearing)
The last couple of days had near record lows in Greater Moncton with temperatures dropping to near the freezing point.
A low of 1.0 C at the airport on Monday was close to the 1947 record of 0.6 C while a low of 0.0 C on Tuesday tied the minimum from 1995.
Fortunately cloud cover prevented frost in most of New Brunswick but another risk is possible by early Wednesday.
Folklore suggests frost can be expected until the full moon in June which is this Friday the ninth.
Ominous clouds near Nova Scotia-New Brunswick border, 03 June 2017 (Dearing)
Weather conditions have been cool and unsettled in the Maritimes over the past several days.
While driving in Nova Scotia on Friday, I encountered everything from clouds and heavy downpours to a clearing sky with bright sunshine to clouds and rain again.
On the way home to New Brunswick on Saturday, I encountered similar conditions.
In Greater Moncton today, the thermometer climbed to a daytime high of only 10.6 C under a dreary sky which is about 10 degrees below normal for early June.
Forecasters say warmer, more seasonal temperatures will return by Wednesday but not before a risk of frost in Southeast New Brunswick by early Tuesday.
Snow covers a vehicle in Aviemore, Scotland, UK, 25 April 2017 (BBC Weather)
Arctic air has enveloped the United Kingdom with heavy snow in Scotland and northern England and near freezing temperatures as far south as London.
Forecasters say snow in late April is not uncommon and actually fell over parts of the country around the same time last year.
Temperatures struggled to reach 10 C today after a hard frost early this morning.
This cold snap is a far cry from record breaking heat earlier this month when the thermometer climbed to 26 C in southern England and a mild March which was the fifth warmest ever for the U.K.
Fall colours past peak, Centennial Park, Moncton, 16 Oct 2016 (Dearing)
It’s not surprising the days gradually get cooler in October but it was a sudden change in Greater Moncton when temperatures went from mild to cold during the last week of the month.
A warm, humid daytime high of 20.5 C on 22 October will undoubtedly be the last time the thermometer climbs above 20 C in this calendar year.
Although a couple overnight lows fell below freezing early in the month, a hard frost was not reported until 27 October.
Almost 50 mm of rain fell on Thanksgiving weekend in Southeast New Brunswick – far less than other parts of the Maritimes such as Cape Breton Island with over 220 mm.
OCTOBER 2016 ALMANAC (at Greater Moncton International Airport, 1981-2010)
Average HIGH 14.5 C
Average LOW 3.6 C
AVERAGE 9.0 C (about 1.4 degrees ABOVE normal)
Extreme HIGH 24.4 C (07 October)
Extreme LOW -2.8 C (28 October)
RAINFALL 99.8 mm (about 10 percent BELOW normal)
(Data courtesy Environment Canada)
Frost covers a maple leaf (Twitter)
Scattered frost has dotted the landscape of Greater Moncton a couple of times in the last week or so.
But the thermometer dipped below freezing early today to -1.5 C which brought widespread frost and effectively put an end to the growing season.
The last time it fell below zero was 15 May which means 2016 had about 142 frost-free days.
A hint of fall colour in Irishtown Nature Park, Moncton, 24 Sept 2016 (Dearing)
Autumn only began a few days ago but it is already feeling fall-like and a frost advisory has been issued for most of New Brunswick.
Environment Canada says a cold air mass will remain over the province with overnight low temperatures approaching zero in some areas.
Frost is expected to be more significant in low lying areas away from coastal waters.
Incidentally, the average first frost date in the fall is 27 September.
The low in Greater Moncton this morning was 2.8 C with patchy frost reported.
UPDATE: On Sunday morning, the temperature fell to 1.8 C.