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There will be snow. Lots of snow.

January 16, 2022 @ 22:07 By: gordon Category: Weather

It’s been a while since I blogged about anything of significance. The weather in Ottawa is going to be rather exciting over the next day or two.

TAF CYOW 170240Z 1703/1724 07010KT P6SM BKN140
FM170600 07012KT 1 1/2SM -SN OVC025
FM170800 06015KT 3/4SM -SN VV007
FM171300 06015G25KT 1/4SM +SN VV005 PROB40 1713/1716 1/8SM +SN
BLSN
FM171600 01012KT 1SM -SN OVC008
FM172100 32012KT 2SM -SN OVC010
RMK NXT FCST BY 170600Z

In simple terms, this TAF basically says that Ottawa is going to get snow. A lot of snow. Starting at about 01:00, or in about three hours’ time from now.

Looking at the various models, it looks like the peak is going to be between about 08:30 and 11:00, which is consistent with the bolded line above, which says that from 1300Z (08:00 Eastern) the wind will be 15 knots gusting to 25 knots from the east-northeast. The visibility is forecast to be about a quarter of a mile with a vertical viability of 500′ and heavy snow. And there’s a 40% probability between 1300Z and 1600Z (11:00 Eastern) that the visibility will drop to an eighth of a mile with heavy snow and blowing snow.

This model is predicting a 1-hour accumulation of 64.6 mm, or 6.5 cm, of snow at 9am Eastern.
This model measures precipitation in terms of rain, while snow is approximately 10 times as much. At 10am Eastern, it is predicting a 3-hour accumulation of 14.7 mm of rain, which is roughly 147 mm of snow or 14.7 cm of snow.

Brace yourself: This is going to suck

January 10, 2017 @ 13:10 By: gordon Category: Weather

I just looked at the radar…


And the aviation forecast:

TAF CYOW 101738Z 1018/1118 12010KT P6SM -SN OVC040 TEMPO 1018/1019 2SM -SN OVC030
FM101900 13012G22KT 3SM -SN OVC030 TEMPO 1019/1020 1SM -SN VV007
PROB40 1019/1020 3/4SM -SN
FM102000 13012G22KT 1/2SM SN VV005 TEMPO 1020/1022 1SM -SN
PROB30 1022/1103 1/4SM +SN VV003
FM110300 14018G28KT 3/4SM -SN BLSN VV007 TEMPO 1103/1107 2SM -SNPL OVC012
PROB30 1104/1107 3SM -FZRA BR OVC015
FM110700 17020G30KT 3SM -SNRA OVC012
FM111100 22020G35KT P6SM BKN030
FM111400 23015G25KT P6SM FEW030
RMK NXT FCST BY 102100Z=

The likelihood that this is going to suck is very high.

No redeeming features

February 23, 2016 @ 22:21 By: gordon Category: Weather

I can see no redeeming features in the forecast for the next day or so:

TAF CYOW 240238Z 2403/2424 05005KT P6SM OVC040 TEMPO 2406/2408 P6SM -SN BKN020 OVC040
FM240800 03005KT P6SM -SN FEW010 BKN020 OVC040 TEMPO 2408/2410 P6SM NSW BKN025 OVC040
FM241000 02005KT P6SM -SN SCT008 OVC020 TEMPO 2410/2414 3SM -SN BKN008 OVC020 PROB30 2410/2414 2SM -SN -FZDZ BR OVC004
FM241400 05010KT 11/2SM -SN OVC008 TEMPO 2414/2417 3SM -SN OVC020
FM241700 06015G25KT 1/2SM SN BLSN VV005
FM242000 07015G25KT 1SM -SNPL OVC006 PROB30 2420/2422 1/2SM SN BLSN
FM242300 07015G25KT 2SM -FZRA BR OVC006
RMK NXT FCST BY 240600Z=

Light snow. Light snow with light freezin drizzle. Moderate snow. Blowing snow. Snow pellets. Light freezing rain. And increasing amounts of wind as time marches on.

Nope, not a single redeeming feature.

Exciting weather for dragonboating

June 10, 2015 @ 16:55 By: gordon Category: Dragonboats, Weather

We’re in for some exciting weather during the next few hours:

TAF CYOW 102040Z 1021/1118 19010G20KT 6SM -SHRA BR OVC080
TEMPO 1021/1023 VRB15G30KT 2SM TSRA BKN008 OVC030CB
FM102300 19010G20KT 6SM -SHRA BR OVC080 PROB40 1023/1024 VRB15G30KT 2SM TSRA BKN008 OVC030CB
FM110100 24010KT P6SM FEW020
BECMG 1106/1108 24010G20KT
FM111400 27015KT P6SM BKN040
RMK NXT FCST BY 110000Z

And there’s a severe thunderstorm watch warning in effect as of the time of this post, and up the Valley they’ve had tornado watches
A quick peek at the radar right now shows that a bunch of rain has passed south of the city, but there’s still a couple of fairly energetic cells making their way down the Ottawa River towards us:

Naturally, I’m supposed to be on the water steering for a couple of dragonboat teams this evening, when it’s probably going to be quite windy and probably rainy. Yay Goretex™!

A few pics of the storm

September 05, 2014 @ 16:04 By: gordon Category: Weather

IMG_3581.JPG

IMG_3577.JPG

IMG_3579.JPG

IMG_3575.JPG

I want no part of this

April 14, 2014 @ 22:47 By: gordon Category: Weather

The forecast for tomorrow has no redeeming features:

TAF CYOW 150238Z 1503/1524 20010KT P6SM SCT020 OVC030 TEMPO 1503/1507 5SM -SHRA BR OVC020
BECMG 1504/1506 29010KT
FM150700 29010G20KT P6SM OVC012 TEMPO 1507/1510 4SM -SHRA BR OVC006
FM151000 31012KT 2SM -RA BR OVC006
FM151500 31015G25KT 3SM -FZRA -PL BR OVC010
FM151800 30012G22KT 2SM -PLSN OVC012
FM152100 30012G22KT 3/4SM -SN BLSN VV008
RMK NXT FCST BY 150600Z=

Basically, that says light rain showers overnight, gusty winds, rain and mist becoming freezing rain and pellets (yum!) around 9am, which will become snow pellets in the early afternoon and finally snow and blowing snow around 5pm tomorrow afternoon.

I want no part of this.

Welcome to 2014, eh?

January 05, 2014 @ 22:16 By: gordon Category: Weather

XFT radar - 20140105 2120L

So, 2014 is off to a bit of an extreme start weather-wise. We saw -27C weather that felt like -40 thanks to the wind last Thursday, and Winnipeg was colder than Mars.

This evening, it’s about -5C and forecast to go above 0C tomorrow. The incoming warm front has been causing the air pressure to plummet the last few hours (the blue line in the graph below) and we can expect to see freezing rain and probably rain overnight and in the morning. A few hours after that, we can expect to see the cold air return with over the course of a few hours, which should make the evening commute rather messy, with the evening forecast to be -24C and a windchill of -33.

If you look at the aviation forecast, you can see the wind change direction from being out of the northeast (050) at midnight local time (0500Z) to coming from the southwest (230) by 8 am (1300Z):

TAF CYOW 060242Z 0603/0624 07015G25KT 6SM -FZRA -SN FEW006 OVC025
TEMPO 0603/0605 2SM FZRA -PL BR BKN006 OVC030
FM060500 08015G25KT 2SM -FZRA BR OVC005 TEMPO 0605/0611 6SM -FZRA BR OVC010
FM061100 10008KT WS010/17032KT 1SM -RA BR OVC003 PROB40 0611/0612 1SM -FZRA BR
FM061300 23020G35KT 2SM -RA BR OVC008
FM061600 25020G35KT P6SM BKN025
RMK NXT FCST BY 060600Z=

And you can see that the wind from 1300Z on is going to be 20 knots gusting to 35 knots (37 km/h gusting to 65 km/h). Ick.

Dress warmly because weather like that can cause frostbite before you realize it.