A potent cold front will be pushing across southern Manitoba from the north-northwest this afternoon. Strong to severe thunderstorms are expected to develop and organise along this front beginning this morning in the Parklands and northern Interlake. By the time the front reaches the RRV mid afternoon to early evening, a line of thunderstorms is expected. Damaging winds will be the main concern as a result for us here. I think the chance that Winnipeg will get some form of thunder is high.
Behind the front, skies will clear for tonight before things cloud up again tomorrow morning. Due to little sunshine in the afternoon, highs are only expected to be around 15-16°C in Winnipeg. With strong northwest winds up to 40 km/h at times, it will feel more like October than July. A few showers are also possible later in the afternoon and evening.
This cool down arrives as the jet stream pattern highly amplifies again in the next few days as seen in the model image below. Generally unseasonably cool conditions are expected in central and eastern parts of North America in the next few days. In contrast, the west will be cooking. Highs well in the 30's and possibly approaching 40°C are expected in the Interior of BC in the next few days.
 |
| Highly amplified pattern returning for a visit. Deep trough over eastern North America, large ridge in the west. Map was retrieved using AWM's Model Viewer |
Thankfully, the extreme cool down looks brief. Temperatures will start warming up beginning mid week as a southerly flow returns. We should reach low 20's on Tuesday and mid 20's on Wednesday. Even warmer air is possible on Thursday before things might cool down a bit to end the week. Still far away so things could change a little bit.
Forgot to mention we will have a shot at a record low maximum tomorrow. Old record is 16.7°C in 1884.
ReplyDeleteYeah, I agree, we certainly do have a very high chance of some sort of storm this afternoon here in Winnipeg. I am quite concerned on the potential for very strong winds with these storms. Could be very damaging with gusts potentially up to 110 km/h. Just hope those around the lakes or in cottage country are aware or make themselves aware of this potential nasty weather this afternoon. Don't like the the cold air coming in behind this front but fortunately it looks brief with much warmer weather as JJ sated moving in by Wednesday.
ReplyDeleteThe cold front with the line of intense thunderstorms is quickly moving southward as 1:15 pm CDT. Watch out for very strong winds. The storms should and I say should move into Winnipeg within the next couple of hours that is of course they don't fizzle out before they get here.
ReplyDeleteStrong line of thunderstorms to hit Winnipeg sometime between 3:30 pm and 4:30 pm. Damaging winds have become the main concern today as expected with gusts at least over 70 km/h, locally over 100 km/h possible. Hail doesn't seem to be a big threat, but can't rule out some small hail. Frequent and intense thunder and lightning likely. Should be a decent event!
ReplyDeleteBehind the leading line, we will see some shower activity associated with a trailing stratiform rain region. Shouldn't last terribly long, but will give us some additional rains. This feature is very common with squall lines like this.
Certainly not the biggest storm Winnipeg's ever had, but I'd call it decent. There were blowing clouds of dust here with the outflow ahead of the storm. Only picked up about 3 mm or so so far.
ReplyDeleteYeah it was rather underwhelming but better than nothing I guess
ReplyDeleteNothing impressive about the storm Saturday afternoon. More hype than anything else. Did not even warrant storm warning as far as i'm concerned. But looks like a bit a cell in moving now as of 12:30 Am with some lightning to our northwest. Interesting.
ReplyDeleteWow, was not expected to be woken up by a thunderstorm tonight!
DeleteStrangely, the thunderstorm last night was not recorded in the METAR observations at the airport. However, I did see the airport was reporting a thunderstorm after 1 am. I'll consider today a thunderstorm day as a result; must've been an error of some sort with the METAR observations.
ReplyDeleteAs for the forecast, skies will be clouding up soon this morning. I'm only anticipating a high around 15-16°C today as a result. There could even be some more showers this afternoon and evening with a few mm possible by overnight tonight. A reminder that the record low maximum today is 16.7°C in 1884 and 1950.
A mix of sun and cloud tomorrow with a high around 20°C or so. Lots of sun on Tuesday again, reaching around 21-22°C.
Today's thundercast update was the easiest this summer! Doesn't look like a chance for storms comes back until at least Thursday. Some models hint at a more active weather pattern returning for southern Manitoba to end the week into early next week.
Oh, and about last night's storm. Looks like the heaviest rains were in the west end with 10 mm recorded in Whyte Ridge and Charleswood. 5 mm at the airport. Only 2.6 mm here in south St Vital.
DeleteJJ, was the unexpected thunderstorm activity last night caused by some sort of boundary off the lakes?
ReplyDeleteThanks, Anon
Didn't have the chance to look into it, but I highly doubt it had to do with the lakes. The storms were probably elevated and not surface-based.
DeleteDon't think I've ever experienced a day this cold in July before personally. Truly feels like April or October out there. Even during the dreadful summer of 2004 we didn't have a day this cold in July.
ReplyDeleteHigh of 15.7°C at the airport today, easily breaking the old record low maximum of 16.7°C.
Yeah, definitely a fall like day, complete with lake enhanced showers! But there was a similar, if not worse mid July day 6 years ago on July 12 2008 but it doesn't show up in the record books as a record cold maximum that day. That day saw miserable wet windy conditions with 10-20 mm of steady rain, and NW winds gusting over 70 km/h in Winnipeg resulting in local tree damage. After reaching a morning high of 16.6C, temperatures were only around 13-14C all afternoon with a driving rain. Once again, during Folk Fest. There were even stronger winds off the lakes with gusts of 90 km/h+ off Lake Manitoba and Lake Winnipeg. This was courtesy of an unseasonably deep 984 mb low that tracked northeast of Berens River.
DeleteI had forgotten about that, but I sure remember it now that you mention it! A few branches were knocked from our tree that time as well.
DeleteYeah, this is bad. Fortunately it won't last. But nonetheless, I don't think it could be more brutal than this here for this time of year.
ReplyDeleteStill not sold of what some models are advertising later this week going into next week as far as potential extended period of above normal temps are concerned. It's basically believe it when I see it.
ReplyDeleteMeanwhile, record breaking scorching heat in BC the last few days to continue. Several locations reached 40°C yesterday including 41.1°C in Lytton, 40.6°C in Lillooet, 40.3°C in Kamloops and 40.0°C in Osoyoos, all records. Mother Nature likes her weather to the extreme these days.
ReplyDeleteWe'll see more sun today but still with lots of lingering cloud at times. Perhaps a shower this afternoon, but the risk is much lower than yesterday. Should manage to reach 19-20°C.
ReplyDeleteFull sunshine returns tomorrow with highs around 22°C. The warmup continues only gradually, with highs around 24-25°C on Wednesday. Overnight lows will be cool over the next couple days, dropping to the mid to high single digits.
Stronger southerly flow returns on Thursday. Should reach around 28-29°C or so. A 30°C day looks possible on Friday, with warm conditions looking to continue on the weekend. That's how things look so far.
Looking at daily temperature and precip records for the summer months, we see that since 1990, Winnipeg has set only 6 new record highs between June 1st and August 31st. Meanwhile during the same period, we've set 9 new daily record lows, 11 record low maximums, and 14 record high minimum temperatures. In addition, since 1990, we've also set 22 new daily rainfall records between June 1st and August 31st. It's an interesting way to look at how our climate has trended over the past 25 years or so. With the lack of record highs, and an increased number of record high minimum temperatures and rainfall records, it points to a climate that has become wetter, more humid, and cloudier. That makes it more difficult to get those extreme hot days that were more frequent or easier to attain when our climate was drier. That's not to say we don't get sunny hot days.. we do. It's just that they're not as frequent, long lasting or extreme as they used to be in a drier climate.
ReplyDeleteWhat I don't get is the higher number of record low temperatures which you wouldn't expect in a cloudier wetter climate. That could be a result of cooler nights following cloudy rain cooled days (like yesterday) Admittedly, this is a simplistic look at our overall climate based on these extremes, and doesn't necessarily reflect what our future climate may bring (which could also see hot dry years) But it's an interesting analysis of what we've been experiencing over the past 25 years or so.
Or, in other words, rounded to the nearest whole number: ~7% of the record highs in the above mentioned period where set in the past 25 years; ~10% of the record lows; ~12% of the record low maximums; ~15% of the high minimums; and ~24% of the rainfall records. These are just the stats, would be cool if somebody could give me some insight behind the stats of how our climate is changing!
ReplyDeleteThanks!
AFew years ago I produced a chart of the 15year moving avg of precipitationFrom1938 to 2008 The increase in precipitation was in excess of 20% Note the first 15 year period covered 1938 tao 1953 the post St John College weather era. Annuaized Peaks in precip Occurred approx 3 yrs after peaks in Icelandic VEI index activity which would imply we have just peaked for at least 3 years.
DeleteRob, you've inspired me to look deeper into the question of moister summers. So far, I've only looked at July. Already, it appears Julys really are in a trend towards being moister at this time; wether that will continue remains to be seen of course. To find this out, I used dewpoint observations. A graph can be found with the following link:
ReplyDeletehttp://blogextra.weebly.com/julymoistening.html
The graph shows the average hourly dewpoint observations through the entire month of July per year since 1953. 10-year and 30-year running averages are included to show the trend.
For what it's worth, here's some interesting discoveries I've made:
I was surprised by how moist July 2012 really was. It was easily the moistest July on record since 1953, and by a large margin. The average hourly dewpoint was 16.5°C, a full 1.0°C higher than the previous moistest July of 1989 which had an average hourly dewpoint of 15.5°C. The 1953-2013 average is 13.8°C. The 1981-2010 normal is 14.2°C.
Since 2000, 4 Julys were in the top 10 moistest (2001, 2007, 2010, 2012) while none were in top 10 least moistest.
Only 3 Julys since 1953 did not feature a dewpoint over 20°C: 1961 (max 18.9°C), 1980 (max 19.2°C) and 1992 (max 18.5°C).
Only 5 Julys since 1953 had an occurrence of dewpoint over 25°C, 3 of which were after 2000 (2005, 2007, 2011). Max hourly dewpoint observation was 26.1°C in 1966.
Interesting analysis JJ.. From your graph, you can see how our average dewpoint has been steadily rising over the past 20-30 years. Since 1990, only 2 Julys have had average dewpoints below 13C. Prior to 1990, that happened a lot more often. Thanks for the quick number crunching!
DeleteCould see severe thunderstorms Sunday with the hotter and likely more humid airmass that will be in place. Sunday looks quite unstable at this point, so we'll see.
ReplyDeleteFor probably a first this year, the latest CPC 6-10 day outlook starting later this week favors an extended period of above normal temps. Still a wait and see thing but for once models showing some hope.
ReplyDeleteLots of sun and light winds today & tomorrow. We'll reach about 23°C today and 26°C or so tomorrow.
ReplyDeleteThe heat returns on Thursday with highs likely around 30-31°C assuming sufficient sunshine. Humidity will also be on the increase, but is not expected to be on the extreme side of things. A cold front will move in late in the day into Thursday night bringing a chance for showers and perhaps a thunderstorm.
Chance of showers and storms continues on Friday with cloudier conditions.
At this point, it appears the warmth will continue next week.
Looks like there will be some chances for severe weather later this week and over the weekend as hot and humid weather moves in.
ReplyDeleteYWG airport sure is struggling today at only 19C while it's roughly 22C inside the city. Not the warmest day but at least it's improving.
ReplyDeleteCertainly not the first time forecasts have busted (been too warm) with a north-northeast breeze this year. Forgot to consider that this morning... We'll see if temperatures spike a bit late afternoon.
DeleteNice to see a forecast a forecast of all 30+ temps (except today). Hope the trend continues so we can get all 30+ forecasts tomorrow.. we'll see.
ReplyDeleteNote that that the sunny forecast for the Friday through Tuesday periods is very optimistic. Yes it will be hot but with that we'll see an increased threat of severe weather especially Friday and early next week. In fact Friday has the chance for one of this year's first organized tornado threats in the RRV. So will certainly be keeping on an eye on that.
ReplyDelete