The last long weekend of the summer season will be ending on a cool and windy note as a strong northwest flow pushes in a fall-like airmass over Manitoba on Monday, along with a few showers. Highs temperatures will only be in the upper teens, with gusty northwest winds up to 60 or 65 km/h at times. Although we can use the rain, rainfall amounts Monday will be light with only a few mm expected in passing gusty showers. Things will clear up Monday night with better weather Tuesday and Wednesday under a mix of sun and cloud and temperatures in the upper teens to 20C.
The second half of the week is looking wonderful as a southerly flow spreads warmer air back into Manitoba. That should bring sunny and dry weather for Thursday through Sunday, along with increasingly warm and windy conditions with temperatures in the mid to upper 20s. In fact, it's possible much of the RRV will be hitting the 30C mark again next weekend, although it will be accompanied by gusty south winds. So if the onset of cooler weather is getting you down, don't worry.. summer is still not quite done yet!
Thanks for the update rob! What is the long range looking like after next weekend? Any sign of a cooldown in the near future? I'm looking forward to fall.
ReplyDeleteWednesday morning looking like a cold set-up for our region. High pressure building in with light northwest flow - combined with dry topsoils will set the stage for some frost potential (as stated in the previous post). Models like NAM suggest lows below 4 C which introduces frost potential. However, higher resolution models like NSSL-WRF are already showing sub-freezing dewpoints moving in Tuesday evening. Feel the model is probably catching on to the soil moisture deficits better than lower resolution models. This afternoon's NWS Grand Forks forecast discussion mentions maintaining frost headlines for their northern warning region. Even EC forecast calls for 3 C.
ReplyDeleteOnly saving grace will be some moisture below 850 hPa, representing broken lake effect stratus. However, cold prone areas (like YWG/XWG) that remain clear may well drop towards 0 C or even slightly below. Late maturing crops could take a hit.. little rain in August combined with below average heat units (due to cool overnight lows) has likely delayed maturation.
Will be important tomorrow afternoon to see extent of any stratus and upstream dewpoints.
Is it possible we could see a below freezing temperature in Winnipeg? The current predicted low is 6C but with that setup it sounds like there's a good chance we could get lower.
DeleteLows next weekend are forecasted at 18C! Talk about a rebound to summer
Public forecast from EC since yesterday evening's issuance was 3 C.. SCRIBE may have been higher.
DeleteLows between +1 to +3 C were common under the ridge this morning. Would expect temperatures to drop off quickly to similar values in rural areas outside the city.. before leveling off - especially in the western RRV.
No lake effect stratus apparent, but upstream dewpoints are higher ( >=3 C), than the subfreezing values some model guidance were showing. High clouds are already streaming in from the NW, but will still allow for radiative cooling until they thicken down to the midlevels by dawn. High pressure center drops into S Dakota, but we retain light WNW for much of the night - only western RRV sees return flow commencing in earnest before dawn. Therefore signs point to coldest conditions over SE Manitoba and eastern RRV.
Overall.. chance for light, scattered frost in central and eastern RRV, and risk of light freeze in cold spots east of PTH 12 (bogs, etc).
Sorry I don't understand all the terminology. Are we at risk of getting a frost at the airport tonight?
DeleteWhen temperatures measured at 1.5 m are <= +2 C, formation of frost on the ground surface may occur during night time (temperatures are coldest right near the surface due to a nocturnal inversion). This is referred to as a frost occurrence. If temperatures as high as 1.5 m are below freezing, this is referred to as a freeze.
DeleteDown to 6C at Winnipeg airport as of 10PM. I think tonight could be a record breaker!
ReplyDeleteLooks like a low of 2.9C at the airport, kind of dissappointing as I wanted to break the record.
ReplyDeleteWidespread near-freezing temperatures overnite from Emerson through Beausejour to Pinawa, resulting in areas of frost formation. Light freeze occurred east of PTH 12 and west of the Whiteshell. Damage likely to any sensitive crops in those regions.
ReplyDeleteNo frost for Winnipeg, most of RRV, southern Interlake and western RRV.. which is good considering there are still considerable heat units to be had these next few days.
Officially low was apparently 1.7C at Winnipeg airport. 9C at the forks. I'm glad they take the measurements from the airport as the forks is artificially inflated.
DeleteCouple of chances for Winnipeg to hit 30C over the next few days. We could hit 30C tomorrow (Sunday) with another sunny and windy day from the south. We drop a few degrees Monday, but a nicer day with less wind and highs around 27C. Then another shot at 30C likely Tuesday, in fact 30-33C possible as we get into another warm southerly flow. That could be the last 30C day of the year as we cool off later in the week.
ReplyDeleteRob did we reach 30C today?
DeleteBased on the long range forecast it looks like there may be a monster storm system coming to dump up to 30mm of rain starting on Thursday along with a major fall like cool down. Rob do you think we will be in the teens for good now starting Thursday? Not many chances at even 20C from that point on. Is fall finally on the way?
YWG hit a high of 29.1C on Sunday.. just short of the 30C mark. Better likelihood of hitting the 30C mark on Tuesday when we climb into the low 30s.. 33C likely for Winnipeg according to most guidance. Record high for Winnipeg tomorrow (Sep 12) is 33.3C in 1952, and we have a good shot at challenging or even breaking that record.
DeleteAs for the rain on Thursday.. models have backed off a bit on the big rain for Winnipeg, but 5-15 mm possible here which would be the most we've seen in weeks. Another shot of rain comes through later Friday through Friday night into Saturday, so we may finally be getting some much needed moisture later this week. Things cool down into the teens over that period into early next week, but signs of temps warming to above normal again later next week. I don't think we're done with seeing 20C temps through the end of September. Usually, we see some 20C temps into early October before we finally cool down for good.
I'm not so sure about temps warming to above normal again late next week, it isn't looking likely. The weather network has highs pinned at 16C into the following weekend. That's closer to average around that time too.
DeleteLast year we didn't cool off until the start of December. That November really was something else..... it was just day after day in the double digits and records falling like flies.
Summer is pretty much over after Wednesday though wouldn't you agree?
I also have a hard time believing we will hit 33C this late in the season, although it is possible as 35C has been reached as late as Sept 27th and 30C as late as Oct 6th.
We'll have to see how extensive the smoke layer is over Winnipeg today which would impact our chances at hitting 33C today. Smoke is a reflector of solar radiation and acts like a cirrus shield in reducing solar strength. That would knock our high temperature down a few degrees depending how thick the smoke was.
DeleteIf the smoke is minor, and today has the ideal conditions for a hot day… Full sunshine, southwest wind, low dewpoints, and dry soils which would allow for maximum heating. Given the temperature profile today, 33C certainly within reason for Winnipeg provided smoke isn't an issue.
Sky looks pretty clear over Winnipeg this morning.. not much smoke aloft. Judging from satellite imagery, webcams and surface obs, the smoke layer doesn't appear that thick or extensive. that would give us a better chance of hitting the 33C mark today. I also think the air-quality advisory will be ended.. doesn't appear that the smoke is thick or extensive enough to pose a general health risk here.
DeleteWell, the smoke did eventually make it into Winnipeg and the RRV, but not until evening. Bulk of the day was generally smoke free with good AQ (2-3 all day). Heat was the bigger issue today than AQ for the RRV. AQ values now dropping this evening.. but only 4 or moderate at Winnipeg and Brandon.
Delete32.2 C as of 2 pm. Can we get that extra 1.2 C before the temperature starts to retreat?
ReplyDeleteThere it is.. 33.8C at Winnipeg airport up to 3 pm, new record high for the day. Still may rise a bit more before 5 pm. Luckily smoke held off so it wasn't an issue to affect temperatures, or air quality which has been good here all day. Smoke levels increasing over SW MB this afternoon which will drift into RRV by evening for awhile before smoke disperses behind cool front overnight.
ReplyDeleteOfficial max of 34.8C at YWG airport today.. hottest day of the year (previously 34.5C on June 2nd) Ideal conditions for maximum heating today.. full solar all day with little smoke aloft to impede heating, dry air (dewpoints dropped to single digits by late afternoon with 20% humidity), dry soils, and a SW wind that allowed a bit of downslope warming. Thicker smoke layer now spreading into YWG and RRV this evening.. you can really see how brown the sky is to the west. That will result in a real orangy brown sunset this evening along with poorer AQ levels. Smoke expected to disperse overnight as winds shift into the north. AQ advisory for RRV today.. but heat was the bigger story. (in fact, one of the advice lines of today's AQ message was NOT to use AC!)
DeleteIf you look at our highest maximum temperatures over the past few years they usually conform to those parameters: dry top soil, dry air, and SW downslope flow.
DeleteNote that moisture has actually started pooling east of the trough with 15-20 C dewpoints in N Dakota.
Well advertized pattern shift commencing.. cool front/trough will stall out just to our southeast as it starts becoming aligned with developing upper SW flow. This is the first prolonged occurrence of such a pattern since early May. Good chance to start putting a dent in our drought conditions as multiple disturbances tracking up from the SW will have access to decent moisture from the Gulf.
ReplyDeleteYup.. haven't seen this upcoming pattern for a long while. Here at my place, I've had only 36 mm (1.4") of rain since Jul 15th, with not one day more than 5 mm since July 11-12th, the last decent rainfall here (24 mm).
DeleteWow it's been that long, yeah I honestly can't remember the last time I've seen a drop of rain, we need it.
DeleteWe smashed that record high today!! That's an incredible temperature for so late in the year! I'm ready for the colder weather!
ReplyDelete36.0C in Carman.. amazing late season heat! Carman has also hit 34.4C on Sep 13 2015, and 32.2C on Oct 5 2011.
DeleteThat's crazy heat! Yeah Winnipeg hit 31.1C on Oct 5th 2011 as well. Our latest date ever to reach 30C was on October 6th in 1879 ( the same year winnipeg recorded the freaky -47.8C reading in December )
DeleteToday's maximum of 34.8C in Winnipeg broke the 1952 record for the day, and was also the hottest temperature for so late in the years since a 35C reading on September 27 1952.
Rob, how's the upcoming pattern change going to play out? I hear of temperatures struggling in the low teens this weekend. I understand we may see more 20C days in the future but would you say that real summer heat is pretty much over now? Does it look like we will be in the teens through the end of the month? What about frost potential?
Yes, in all likelihood, Tuesday was our last day of 30C heat this year.. Pattern change coming up Friday through the weekend with generally near to below normal temps expected through the end of Sept according to latest outlook from CPC (although we briefly rise above normal next Tue/Wed ahead of another area of low pressure to our southwest. Looks like the pattern change will also finally result in above normal precip over the last half of Sept over us as the storm track sets up near us or over the Dakotas with a SW jet tapping moisture from the SW US.
DeleteThanks Rob. I keep forgetting normals are below 20C now. So basically we have a shot of cold air this weekend, then more seasonal values next week, but am I correct in saying we get another shot of cold air for the following weekend again?
DeleteSo I'm wondering if we are almost done with 20C days too now? If we are staying below normal through the end of September could we be looking at a cold October this year? I'm wondering if we'll see snow in October this year. The last three octobers have seen no snow at all so I'm hoping we'll get some this year.
Rob, just how cold is Saturday looking? The weather network is saying a high of 10C on Sunday!! Is it really possible it's going to be that cold?
ReplyDeleteSorry I meant Saturday not sunday
DeleteYes.. Saturday looking quite chilly with rain tapering to patchy drizzle, northerly winds and overcast skies.. temps steady around the 10C mark. Fall-like for sure.. but I think people won't mind if it means a decent rain which we really need.
DeleteYes I'm looking forward to the arrival of fall like conditions Rob! Overall, there is no extended period of above normal temps in the long range is there? Do you think we will be below normal into early October?
DeleteRob. Regarding the next 2 weeks or so. I see we have a cold and rainy weekend ahead of us, but there will be a warmup through the middle of next week. What is to happen after that? Will we be cooling down again for the end of the month?
ReplyDeleteLooks like it.. although we'll be averaging closer to normal with some above normal days interspersed with below normal stretches. The core of the cooler air will be further west over AB/SK
DeleteGlad to hear we will be getting some cooler fall weather, too bad we aren't getting snow yet!
DeleteFinally looking at a decent widespread rainfall over all of southern MB Friday through Friday night into Saturday morning. Looks like a general 20-35 mm for most areas with locally heavier amounts of 50 mm thanks to embedded thunderstorms firing up over ND later Friday into Friday evening spreading into srn MB (mainly closer to US border)
ReplyDeleteAs for Winnipeg.. models are all over the place in terms of amounts, but generally looks like 25-40 mm from Friday afternoon into Saturday morning, with the bulk of rain falling Friday night when it could be heavy at times. Some models show heavier amounts due to embedded convection moving in Friday evening (GDPS shows over 70 mm for us!) Here are the various model outputs of rainfall for Winnipeg through midday Saturday.. (12Z or 18Z run)
RDPS... 32 mm
GDPS... 72 mm
NAM.... 43 mm
GFS.... 23 mm
ECMWF.. 26 mm
SREF... 18 mm
GEPS... 41 mm
Multi-model average is 36 mm. Taking out the highest and lowest values gives a mean of 33 mm. Whatever the case, it'll be the most significant rainfall here in weeks!