Thursday, May 31, 2007

Weekend forecast flips

Quite the change in the Winnipeg area forecast for the upcoming weekend.. Yesterday, the forecast was calling for straight rain Saturday through Sunday. Today's forecast now calls for nothing but sunshine all weekend! Why the major flip? The short answer is that there was a significant change in EC's computer model solution for the upcoming weekend over southern MB. Yesterday's solution had a slow moving upper low hanging around the Dakotas all weekend long, putting Southern MB in a moist unsettled cyclonic flow with rain through the period. Today's model solution now is pushing that upper low further south and east into Minnesota over the weekend, taking the wet weather with it and leaving southern MB with a sunny dry forecast now. Remember, forecasts for the Prairies beyond tomorrow are no longer produced locally in Winnipeg, but are automatically generated from model output from Montreal. That's why long range forecasts can swing wildly from day to day, depending on how stable the model solution is for a particular period.

So, as far as this weekend is concerned, which solution do you believe, rain or sun? Well, probably neither solution is completely right.. and the best guess is probably something in between the two. Looking at the pattern, it looks like we'll still be seeing a lot of cloud on Saturday along with a chance of showers as the remnants of that upper low over the Dakotas starts moving out. Sunday looks like the nicer day with a better chance of sunshine and warmer temperatures as the upper low finally pulls away. As always though, only Mother Nature knows for sure...

Wednesday, May 30, 2007

Gloomy wet weather to continue

It's been a very wet and gloomy stretch over the past 10 days or so, and it doesn't look any better for the next few days either. A stubborn slow moving upper low pressure area over the Dakotas will maintain a cyclonic flow of cloudy cool and unsettled weather over southern Manitoba through the rest of the week into the weekend. Periodic showers will be possible every day, adding to the already soggy rainfall totals of the past two weeks. Some parts of south Winnipeg and southeastern MB have seen over 120 mm of rain in May, twice the average for the month. Luckily, dry conditions earlier in the spring have helped to minimize widespread flooding problems.. however the wet weather is starting to become a concern over southern and eastern sections of the province which have been hardest hit in recent days by heavy rain and lack of sun.

Note that June is normally the wettest month over southern Manitoba as weather systems over the Dakotas tap warm and humid air spreading north from the American midwest, creating showers and thunderstorms over the southern Prairies.

Transcona site joins Winnipeg mesonet

Another personal weather station (PWS) has come online in the Winnipeg area.. this one in Transcona (click here for data) I just noticed it this morning on my Winnipeg area temperature map plot. That helps to fill a big hole in the east end of the city that did not have any weather data up to now. Winnipeg now has at least 10 PWS sites around the city reporting real time data online to augment the official weather observations from Winnipeg Airport and Winnipeg Forks. Great to see, and welcome to the Winnipeg mesonet!

Personal weather stations are becoming more and more popular, where private citizens or organizations are purchasing their own weather stations, and posting their data automatically to the web for anyone to see in real time. It's a growing hobby, and one that is fast gaining interest from many users who rely on quick and reliable real time weather information from more and more sites. This is especially important for rainfall measurements which can vary widely even within a city itself. (as we've seen this past week or so..)

Friday, May 25, 2007

Snow?!

Parts of Winnipeg saw some snowflurries early Friday as a band of lake-effect cloud developed off Lake Manitoba (see image.. CWXN denotes Winnipeg) The good news is that the cloud prevented the city from seeing frost, which occurred in other parts of Southern MB which cleared out overnight. Oh well.. could be worse.. Calgary had 10-20 cm of the white stuff yesterday!

Tuesday, May 22, 2007

Thunderstorms sweep across Southern MB

An area of thunderstorms swept across southern MB last evening and overnight bringing locally heavy rain and hail in some areas. The thunderstorms erupted over northern North Dakota last evening and moved into southern MB last night, reaching Winnipeg after midnight. Marble size hail was reported over southwestern MB with the storms, while generally it was heavy rain further east.

Here in Winnipeg, it looks like thunderstorms hit the south end of the city the hardest with St Vital reporting 31 mm overnight, and Ft Richmond 33 mm. Elsewhere across the city rainfall amounts were generally around 15-25 mm. Some rainfall amounts from the Winnipeg area overnight included...

Ft Richmond......... 33 mm
St Vital................... 31 mm
Fort Whyte ........... 24 mm
Dugald.................... 24 mm
Bird's Hill............... 23 mm
U of M ................... 21 mm
Whyte Ridge ........ 19 mm
U of W ................... 18 mm
East St Paul........... 17 mm
Starbuck................ 16 mm
Charleswood......... 14-16 mm
Selkirk................... 15 mm
Stony Mountain.....14 mm
Stonewall............... 12 mm

Heavier rainfall amounts were recorded southwest of Winnipeg, including

Belmont............. 41 mm
Snowflake.......... 38 mm
Miami................ 37 mm
Morris............... 37 mm

This won't be the last of the rain either. More showers are expected to develop this afternoon, with locally heavy rainfall a possibility again across the Red River valley. Unsettled weather is expected to continue most of the week, along with cooler conditions. Looks like Mother Nature is making up for her warm dry start to spring!

Saturday, May 19, 2007

Gimli webcam added

I've added a nice webcam shot of Gimli harbour to my webcam page. This will give a nice view of the weather in "cottage country", plus wave action on Lake Winnipeg. Thanks to the person who let me know of this webcam link on a previous blog entry.

Gimli webcam page available at: http://www.nihm.ca/webcam_gimli.html

Friday, May 18, 2007

Arctic cold front surging south..chilly weekend on tap

Enjoy those mild temperatures early this morning.. because they will soon be history as a sharp Arctic cold front drops southward across southern Mb this morning, ushering much cooler air from the north. As of 9 am the front has pushed through Winnipeg with northerly winds and temperatures steady near 15C (17C in Charleswoood) However just to our north, it was down to 12c in Selkirk and 8C in Gimli, with even colder readings of +4c through the interlake. This surge of colder air is pushing south faster than predicted, so that forecast high of 26C for Winnipeg is not likely to happen.. instead look for temperatures to remain steady or fall through the day. (Update: forecast for Winnipeg just amended down to a high of 18C)

This cold airmass will be fully entrenched over southern MB by tonight just in time for the long holiday weekend. Dress warmly if you're camping this weekend as daytime highs will only be in the low teens, and nighttime lows just above freezing. Showers are likely by holiday Monday.

Wednesday, May 16, 2007

Cooler and unsettled for May long weekend..

Well, the May long weekend is approaching, and you now what that means.. high gas prices and lousy weather! It will be especially disappointing after 2 warm dry days to end this week with temperatures in the mid twenties on Thursday and Friday. Unfortunately, a cold front will push through from the north Friday evening ushering in much cooler air from the north Friday night into Saturday. Temperatures will only be in the low to mid teens on Saturday along with mainly cloudy skies. On Sunday somewhat milder air will be trying to work in from the south, but that will give rise to more clouds and an increasing chance of showers Sunday into Monday. There could even be some thunderstorm activity Sunday night into Monday. Hey, it's the May 2-4 weekend in southern MB.. what else would you expect??

Tuesday, May 15, 2007

Blustery evening

Boy what a change from that nice afternoon today.. things have turned quite blustery and cool this evening as a secondary cold front pushed in from the north. Wrap around cloud is advancing in from the north with radar showing some scattered showers through the interlake which could move into Winnipeg area this evening and overnight. Hopefully skies stay cloudy most of the night, otherwise if skies clear and winds drop, we could be seeing some frost early tomorrow morning.

Saturday, May 12, 2007

Severe Thunderstorms in Saskatchewan

Locally severe thunderstorms developed over southern SK this afternoon, with an impressive supercell thunderstorm southwest of Moose Jaw near Gravelbourg in the evening. Cloud tops were at least 50,000 ft high with this storm with 25 mm hail reported in a couple localities. Unfortunately, EC radar was unavailable over southern SK due to problems with transmission lines to the radar sites.

Southern MB will see the remnants of these storms on Sunday with showers and possible thunderstorms moving in a narrow band along the TransCanada corridor. Note that SPC is carrying a slight risk of severe thunderstorms over southeast MB for Sunday.

Wednesday, May 09, 2007

Record hot day across Southern MB

A WARM SOUTHWESTERLY FLOW BROUGHT RECORD BREAKING DAYTIME HIGHS TO MANY PARTS OF SOUTHERN MANITOBA TODAY (MAY 9). A COLD FRONT SWEEPING ACROSS THE PROVINCE TONIGHT WILL BRING COOLER TEMPERATURES TO THE PROVINCE FOR THURSDAY.

NEW RECORD HIGHS SET MAY 9TH: (old record in brackets)

WINNIPEG INT'L... 31.3 C (30.7 C 1992)
DAUPHIN.......... 31.7 C (28.3 C 1959)
GIMLI............ 31.3 C (26.7 C 1971)
PINAWA........... 30.0 C (28.0 C 1992)
MELITA........... 29.8 C (23.0 C 2001)
SWAN RIVER....... 31.2 C (28.3 C 1959)
GRETNA........... 30.5 C (26.1 C 1958)
PILOT MOUND...... 30.2 C (30.0 C 1992)
SPRAGUE.......... 29.6 C (29.4 C 1976)
FISHER BRANCH.... 30.3 C (27.0 C 1985)
NORWAY HOUSE..... 26.5 C (23.3 C 1908)

Tuesday, May 08, 2007

A taste of summer!

Beautiful weather across southern MB today and tomorrow, with summerlike temperatures in the upper twenties today, and likely hitting the magic 30C mark tomorrow! Pretty early for this type of heat, but not unprecedented.. as we've seen 30 degree temperature as early as April 18th here in Winnipeg (30.5C April 18 1987). We won'trhit a record today (which is a scorching 35C back in 1874!) but the record high for tomorrow (May 9th) is 30.7C in 1992, so we have a good chance of tying or breaking that record!

Sunday, May 06, 2007

Southwest MB gets soaked..

Southwest MB got a soaking rain today with reports of 20-30 mm near the SK border, including the Melita and Virden areas. Further east, we just got trace amounts today in the Red River valley after 20-30 mm over the past couple of days.

Note that I cleaned out my rain gauge today, so Rob's Obs rainfall amounts should be more reliable with our next rain event (which may not be until late in the week). Look for dry and warm conditions this week, with summerlike temps possible approaching the 30C mark by Wednesday.

Saturday, May 05, 2007

More rain on the way...

A large area of rain over North Dakota (see image) is spreading north into southern MB tonight and will bring steady rain to the Red River valley tonight into Sunday morning. The rain may be heavy at times, possibly with some embedded thunderstorms, with amounts of 15-25 mm possible by morning especially over southern and western sections of the Red River valley.

Friday, May 04, 2007

Rainfall update

Rain is moving through Winnipeg this afternoon, with about 7 mm reported by most sites across the city as of 3 pm. Note that I'm currently having problems with rainfall readings from my Rob's Obs site.. I just checked the rain gauge and some bird has decided to use it as its own personal bird seed collector! So the gauge is jammed with bird seed and not reporting rainfall accurately. I'll try to clean it out over the next day or so, but until then, Rob's Obs rainfall will be inaccurate. Look at the PJ school site for more accurate Charleswood rainfall.

As for this rain.. it should gradually taper off tonight then we get a few showers Saturday before another batch of rain moves in Saturday night into Sunday from the Dakotas. Models are showing a real soaker out of this Saturday night event, especially over southwest MB with 30-50 mm possible, likely with embedded thunderstorms. Not the best timing on a weekend, but it's sure welcome for farmers..

Thursday, May 03, 2007

Rain on the way..

After 4 weeks with little or no rain over southern Manitoba, it appears that we'll be seeing our first significant rain event over the next few days. A first wave of rain is expected to move in from the southwest on Friday, spreading into the Red River Valley by afternoon, and Winnipeg by mid to late day. This first band of rain may bring 10-20 mm of rain to Southern MB Friday into Friday night. On Saturday, a second wave of showers and thunderstorms, locally heavy over North Dakota, and forecast to spread northward into southern MB by Saturday afternoon. This second wave of rain is forecast to bring heavier rain amounts, possibly 15-30 mm over portions of Southern MB Saturday afternoon into Saturday night. The rain is expected to move out of Southern MB on Sunday as the main low pressure system moves off to the northeast.

Summing up.. rain moving in from the southwest on Friday into Friday night with 10-20 mm possible.. a second wave of rain, sometimes heavy, developing Saturday into Saturday night, with 15-30 mm possible.. heaviest amounts south and west of Winnipeg. Total rainfall amounts over the weekend ranging from 15-25 mm Red River valley with 25-40 mm possible over southwest MB. At least, that's what current models are predicting.. we'll see if it works out. Note that we'll be experiencing a sustained southeast flow Friday and Saturday, which will be advecting some of those higher 10-13C dewpoints over the central plains northward into southern MB, especially southwest MB. This should help fire up some of that convection over the next couple of days.

Tuesday, May 01, 2007

Rain fails to ease fire threat..

RAIN over much of the province did little to dampen the forest fire threat in southern Manitoba, a government official said Monday. Tom Mirus, Manitoba Conservation supervisor of field services, said scattered showers and cooler temperatures only delayed the spread of the largest fire burning in the southeast corner of the province -- it did nothing to put it out.

"They had a sprinkle of rain and that was it," he said at a media briefing. "It's keeping us pretty busy." What cloudy skies did give firefighters was a chance to get the upper hand on the blaze -- it's burned 3,800 hectares so far -- before sun and wind return to the forecast for the rest of the week.

On the plus side, there were no new fire starts reported Monday. Mirus said the province's biggest forest fire started as three separate ones in the Vassar area over the weekend, but quickly spread to burn as one. The fire is spreading north from an area near the town of Vassar toward the tiny hamlet of Badger, although about six kilometres still separate the community from the flames.

"We don't feel (Badger) is threatened at this time," Mirus said, adding firefighters are doing their best to protect the few homes and cottages in the area. As of Monday only people bothered by smoke had left the area. The cause of the fires remains under investigation. Four investigators are on the scene trying to trace who was responsible. A conviction for deliberately setting a fire carries a maximum fine of $10,000.

Mirus also said conditions are still tinder dry and ripe for more fires as there has been little precipitation since the snow melt. Spring-time foliage has yet to bud, meaning there is little shade or greenery to slow the spread of fire through grass, deadfall and garbage. Open fires are prohibited until Nov. 15 unless a burning permit is obtained and only approved fire pits are used, such as campfire grates in provincial campsites.

Mirus also said that of 35 fire grass and forest fires reported so far this year, all were caused by people. The biggest culprits are ATVs running through the forest and hot mufflers igniting dry grass. "Often they don't know they're started a fire," Mirus said of ATV riders. "It's major headache for us." Mirus said the fight against the Vassar fire has so far cost $250,000. Eleven water bombers, four helicopters, nine bulldozers and scores of firefighters are trying to put it out.

On Saturday, community members and fire crews fought a smaller blaze with water bombers and water tank trucks, in a desperate effort to stop the fire from spreading to backyards and towards their homes. Some residents of the town lost sheds and fences to the blaze, about 135 kilometres southeast of Winnipeg in the Rural Municipality of Piney. The blaze moved north, away from town, but then merged with two other small fires to produce the province's worst forest fire of 2007.

To put it into perspective, last year 35 fires had also been reported by this time, but only 174 hectares had been burned. To date, all fires in Manitoba this spring have burned 4,300 hectares.

From the Winnipeg Free Press