Wednesday, October 31, 2012

Cool October marks first below normal month in Winnipeg since May 2011

October 2012 temperature
summary for Winnipeg
A cooler than normal October will go down as the first below normal month in Winnipeg since May 2011.. or 17 months ago. Over that time, Winnipeg has seen 16 consecutive months near or above normal including 14 straight months above normal from July 2011 to August 2012, an unprecedented stretch of warmth in Winnipeg since records began 140 years ago in 1872.  October finished with a mean temperature of +4.0C, or about 1.3C below the normal October mean of 5.3C (based on 1971-2000 averages).  The bigger story for October was the return of some much needed precipitation, with 57.5 mm recorded at YWG airport, about 20 mm wetter than normal for October. It was the first wetter than normal month in Winnipeg since May, and comes after an exceptionally dry September  that was the second driest on record. Precipitation amounts were even greater elsewhere in the city with 72 mm at the Forks and 85 mm in Charleswood. Outside the city, the big weather story in October was the early October snowstorm on the 4th that brought up to 30 cm of heavy snow over southeast MB.    

Wednesday, October 24, 2012

Colder weather on tap..

Colder weather is on tap over southern Manitoba for the next few days as a cold northwest flow sets up behind a storm system intensifying over northern Ontario Thursday.  This system will drag the coldest air of the season so far over southern Manitoba, with daytime highs only near or slightly above freezing, some 5-7C below normal for late October.  The cold weather will be accompanied by mainly cloudy skies and occasional flurry activity, with locally heavier snow bands possible to the southeast of Lakes Winnipeg and Manitoba. The cold weather is expected to persist through the weekend into early next week, with a moderating trend possible later next week.

Sunday, October 21, 2012

More rain Tuesday.. turning colder by late week with snow possible..

60 hr GLB valid Tuesday morning
Oct 23rd with rain spreading into
southern MB
Generally fair and seasonable weather is expected today and Monday, before another round of wet weather moves in Tuesday. After that, things will get progressively colder through the end of week into next weekend, with well below normal temperatures expected through the end of October. The colder weather will bring some snowflurries later this week, with some accumulating snow possible at times.  For today, cloudy skies and scattered light showers this morning will give way to thinning clouds this afternoon, with afternoon highs near 10C accompanied by northwest winds of 20 km/h.  Morning sunshine Monday will give way to increasing clouds ahead of the next system, which is expected to spread some rain over southern MB overnight Monday into Tuesday. At this point, it looks like about 10-20 mm of rain is possible for Winnipeg  and the RRV, with higher amounts of 20-30 mm over southwest MB into the interlake regions.

Yikes!  132 hr GLB valid Friday
Oct 26th shows potential snowstorm
over southern MB/NW Ont
Rain will gradually pull off Wednesday followed by a northwest flow of colder air for Thursday into the weekend. This will be the coldest outbreak of the season so far, with high temperatures only near freezing or even below through the weekend into early next week, along with the possibility of accumulating snow. In fact, long range guidance is suggesting the potential of a significant snowstorm over portions of southern MB or NW Ontario by Friday. Stay tuned..       

Thursday, October 18, 2012

Another soaking rainfall over southern MB.. more rain and wind today

A strong low pressure system over northern Minnesota brought another soaking rain over southern Manitoba Wednesday into last night, with amounts of 15 to 40 mm recorded in the past 24 hours.  Amounts were heaviest along the western RRV with amounts of 30 to 40 mm recorded from Portage through Carman to Morden. Lesser amounts fell in Winnipeg with about 15 mm through midnight. More rain is likely today as another batch of showers moves in this morning with 5 to 10 mm possible by evening, along with increasing northerly winds gusting to 70 km/h at times this afternoon into this evening.  The rain has brought some much needed moisture to southern MB, after an exceptionally dry September that saw only 4 mm fall all month in Winnipeg. Rainfall this month is now up to 36 mm at the airport as of this morning, and 50 mm at the Forks. Normal October precipitation is 36 mm, so this month will be the first month since May that has seen above normal precipitation in Winnipeg.  Things are expected to dry out for the weekend into early next week, but long range guidance is hinting at the possibility of a strong storm system moving across the northern Dakotas by the end of next week bringing another round of significant  precipitation over southern MB, with a soaking rain possibly changing to snow.  Stay tuned..   

Thursday, October 11, 2012

Brisk southerly winds Friday to usher in milder weekend..

After more than a week of below normal temperatures, conditions will be becoming milder this weekend as winds shift into the south and southwest.  Temperatures will finally be returning into the double digits after being generally in the single digits since Oct 3rd.  The change to milder weather will be heralded by strong southerly winds Friday gusting to 60 or 70 km/h, which combined with afternoon temperatures in the 5-10C range will feel quite brisk. Things will feel a lot milder on the weekend, as temperatures climb into the low to middle double digits, along with lighter winds and sunshine. Normal highs for this time of year are 11C, with normal lows of 0C.  Near to above normal temperatures are expected early next week, before a return to colder weather by the middle to latter part of the week.  

Sunday, October 07, 2012

More rain on the way.. with some snow possible Monday night

GEM precip type forecast for
Monday evening Oct 8 2012.
Green is rain, blue is snow,
yellow is wet snow/rain
A clipper system over northern Saskatchewan will track southeastward into southern MB overnight and Monday bringing another round of much needed precipitation over the region. Rain from this system will spread into western MB this evening and into the RRV overnight, continuing though Thanksgiving Monday. Rain will change over to snow over higher elevations of western MB Monday with some accumulations likely over the Duck and Riding Mountains. Rainfall amounts of 10 to 20 mm will be possible through much of southern MB, especially from western MB highlands into the RRV, including Winnipeg. By Monday night, colder air wrapping in behind the system will change rain over to wet snow even over the RRV, with a coating of wet snow possible by Tuesday morning. Below normal temperatures in the single digits will persist through the week, before some moderation by next week.     

Thursday, October 04, 2012

Early season snowstorm slams southeast Manitoba

Heavy snow and downed trees
made roads nearly impassable
near Vassar, MB - Oct 4 2012
A powerful early season snowstorm slammed southern Manitoba Thursday Oct 4th bringing significant snowfall to southeastern parts of the province. Rain from the system changed to snow early Thursday and continued through the day, with accumulations of 10-30 cm reported over the Steinbach, Whiteshell, Sprague and Bissett regions. Snow was mixed with rain further west over the Red river valley with a slushy coating of snow in Winnipeg by afternoon.  Strong northerly winds gusting to 60 or 70 km/h accompanied the storm, which combined with the heavy wet snow resulted in tree damage and power outages over much of SE Manitoba, with numerous hydro poles and hydro lines downed.  Road conditions over southeastern MB were poor due to the heavy snow and poor visibility, with travel not advised from Steinbach to the Ontario border. (see some impressive snowfall photos from Steinbach Online photo gallery showing extent of snow over southeast Manitoba) 

Snowfall totals from the storm included..

Satellite image Oct 6 2012 showing
extent of snowcover over SE MB.
Note also bands of lake effect snow
off Lakes Winnipeg and Manitoba
which set up Friday behind storm.

Sandilands ............. 30 cm (trees down)
Hadashville ............ 30 cm (see photo)
Woodridge ............. 30 cm (see photo)
La Broquerie .......... 27 cm
Falcon Lake............ 25-30 cm (est) 
Vita ........................ 25 cm
Pinawa ................... 20-30 cm
Bissett .................... 20 cm
South Junction ........ 20-30 cm  /nr Sprague/
Steinbach ...............  8 cm

Up to a foot of snow fell over parts
of  SE Manitoba Oct 4 2012.
The early snowfall, although an inconvenience, brought some much needed moisture to the region, which has been exceptionally dry over the past 6 weeks.  The snowfall brought relief to firefighting efforts in the Vita area, which had been evacuated just two days earlier by windswept wildfires.  In Winnipeg, about 8 mm of rain and wet snow was recorded at Winnipeg airport by evening, with 10-20 mm of precipitation reported across the city (19 mm at the Forks and 18 mm at my site in Charleswood)

Early Snowfalls over Winnipeg and southern MB

Snowfalls this early are unusual, but not unprecedented.  Winnipeg has seen measurable snow as early as Sept 20th when 1.5 cm was recorded in 1945. On Oct 2 1950, Winnipeg reported 12.7 cm of snow, while 13.8 cm of snow was recorded during a wintery blast on Oct 7-8, 1985. Heavier snowfalls have been recorded elsewhere over southern Manitoba during early October and September, especially over the higher elevations of SW Manitoba. Most recently, a record early snowstorm on Oct 5 2005 dumped 20-45 cm of snow over southwest MB, heaviest around the Pilot Mound area. October 1959 saw 3 major snowstorms dump over 100 cm of snow over SW Manitoba, in what was the snowiest month on record in Brandon. One of the earliest snowstorms ever recorded in southern MB occurred on Sept 12-13 1903, when 10-30 cm of snow fell over higher elevations of western MB near the SK border. 

Early season snowfalls in Winnipeg (since 1872)

Sep 20 1945 * ......  1.5 cm   (see note below)
Sep 24 1984 ........  5.8 cm
Sep 25 1872 ........ 18.3 cm
Sep 29 1908 ........  5.1 cm
Oct  1 1996 .......... 4.0 cm
Oct 2 1950 .......... 12.7 cm
Oct 4 1952 ........... 8.6 cm
Oct 5 1876 ........... 11.4 cm
Oct 5 2005 ............  7.0 cm 
Oct 7-8 1985 ......... 13.8 cm

* Officially, the date of this earliest snowfall is listed in the climate archives as September 19th 1945.  However, the snow actually fell in the pre-dawn hours of Sept 20 1945 from 4:20 am to "breakfast time" according to the Winnipeg Tribune. Prior to July 1961, precipitation that fell before 630 am was included in the previous day's precipitation total. 

Tuesday, October 02, 2012

Storm system to bring significant rain.. and (gasp) snow.. to Red River Valley and SE Manitoba Thursday into Thursday night.

4 km hi-res NAM image valid
15Z Thursday morning. NAM is
most aggressive on storm intensity
and snowfall over southern MB
A major storm system is forecast to develop over the eastern Dakotas Wednesday, tracking into northern Minnesota Wednesday night into NW Ontario Thursday. This system is poised to bring the most significant precipitation to the Red River valley and SE Manitoba in several weeks, and the moisture will be most welcome.  Current model guidance is showing anywhere from 10 to 50 mm of precipitation may fall with this storm system Wednesday night through Thursday and Thursday night. The problem is there are indications that some of this moisture may fall as snow, and the snow could be significant over portions of the RRV and SE MB, as well as neighbouring northeast ND, northern MN and NW Ontario.  Rain from this system is expected to spread into southern MB from North Dakota Wednesday night and continue Thursday, with increasing northerly winds bringing colder air into the system as it tracks towards Lake of the Woods. Rain will likely mix with or change to snow Thursday into Thursday night, with some slushy accumulations possible.  The changeover to snow is still difficult to predict, since models differ on the strength and track of the main storm system, and the intensity of the associated precipitation. If the changeover to snow occurs earlier in the day Thursday as some models suggest, snowfall could be significant over portions of the RRV and SE MB. Whatever the case, it will be an important system to monitor over the next day or two. Stay tuned.

UPDATE 2: Winter storm warning in effect for southeast Manitoba, including Steinbach, Whiteshell and Sprague regions. 10-20 cm of snow possible Thursday into Thursday night with up to 30 cm possible in Sprague region.  Winter storm warnings in effect for northeast ND including Grand Forks, as well as northwest Minnesota for possible 6-12" of snow. 

UPDATE 1:  NWS Grand Forks has issued a winter storm watch for northeast ND and northwest Minnesota up to the Canadian border for potential of 6" (15 cm) or more of snow Thursday into Thursday night. Special weather statement issued for the Red River valley and southeast Manitoba for potential early snowfall. A special weather statement is in effect for Kenora and Red Lake for possible 5-10 cm of snow or more Thursday night into Friday.

Wild winds whip wildfires across southern MB.. moisture desperately needed

Winnipeg firefighters battle brush fire
off Loudon Rd in Charleswood
Tuesday Oct 2 2012
Strong southerly winds gusting up to 85 km/h in Winnipeg whipped several wild fires today across southern Manitoba, including two in Charleswood.  A grass fire developed off Charleswood Rd south of Wilkes Ave late Tuesday morning, before a larger brush fire flared up off Loudon Rd, also south of Wilkes around the noon hour. The strong south winds blew heavy smoke across Wilkes Ave into Tuxedo and SW Winnipeg.  The fires were eventually controlled by Winnipeg firefighters, who had to truck water in to fight the blazes.  Several other wildfires erupted across southern MB Tuesday, the most serious near Vita MB in the southeast part of the province. That fire destroyed 3 homes and a bridge, and led to a temporary evacuation of the entire town of 300 inhabitants before residents were allowed back after winds shifted into the west.

Extremely dry conditions over the past month, together with low humidity have left tinder dry conditions across southern MB, creating dangerous fire conditions when strong winds develop.  Significant moisture is desperately needed across southern MB, and there is a potential storm system brewing late Wednesday into Thursday that may bring the most significant precipitation over the Red River Valley and SE Manitoba in several weeks. Stay tuned..        

Monday, October 01, 2012

One last warm blast Tuesday.. then turning sharply colder and unsettled Wednesday through the rest of the week..

It's going to be an interesting week of weather coming up over southern MB as a significant pattern change evolves by mid week.  A intensifying low pressure system over southern Saskatchewan will track through central Manitoba Tuesday, bringing a strong southerly flow of warmer air over southern MB. Southerly winds will gust to 60 or 70 km/h over the Red River valley Tuesday including Winnipeg, which combined with the very dry conditions and low humidities will make for dangerous fire conditions. The gusty south winds will draw up warmer air with afternoon highs in the low to mid 20s.. some 10C above normal for this time of year. But that will be the end of 20C temperatures for awhile.. possibly the rest of the year. A sharp cold front will push through Wednesday morning with northerly winds bringing in much colder air into southern MB. Temperatures will struggle in the low teens Wednesday, falling into the single digits by evening along with a chance of some rain.  Temperatures will remain in the single digits for highs Thursday into Thanksgiving weekend, with even a chance of some rain or wet snow over portions of the RRV Thursday into Friday morning.  Enjoy the warm day Tuesday.. big changes are on the way this week!

September 2012 finishes as 2nd driest September in 140 years.. Above normal streak extends to 15 months..

September 2012 will enter the record books as the 2nd driest September ever recorded in Winnipeg since records began in 1872. The monthly total of only 4.0 mm was less than 5% of normal for September (average = 52 mm) and was second driest only to September 1948 at 1.3 mm. The dry weather has persisted for 6 weeks now, with the last appreciable rainfall back on August 15th when 9 mm was recorded at YWG airport. The dry weather comes on the heels of a dry summer that saw only about half our normal rainfall. This has left soil moisture conditions bone dry, and significant rainfall of 50 mm or more is desperately needed to replenish soil moisture levels. September was Winnipeg's 4th consecutive drier than normal month, with rainfall deficit now standing at 153 mm since June 1st.

Top 5 driest Septembers on record (Winnipeg) - since 1872 

1. 1948 ..... 1.3 mm
2. 2012 ..... 4.0 mm
3. 1938 ..... 6.1 mm
4. 1897 ..... 8.6 mm
5. 1976 ..... 9.9 mm

September  2012 also finished slightly above normal thanks to some warm weather at month's end that boosted the monthly average to 12.6C, or about 0.3C above normal. That extends the monthly above normal streak to an unprecedented 15 straight months in Winnipeg, going back to June 2011.