Matthieu, Author at A Weather Moment • Page 4 of 39

North Dakota Sees First Significant Tornado Day this Year

July 5, 2015July 5, 2015 Matthieu Leave a comment

Last Saturday, on June 27^th, North Dakota saw its first tornado outbreak of the year where 19 twisters touched down across the state.

[map autofit=”1″ disable_scrollwheel=”1″] [pin tooltip=”Roseisle”]Roseisle, Manitoba[/pin] [pin tooltip=”Pisek”]Pisek, North Dakota[/pin] [pin tooltip=”EF-2 occurred just west of here”]Holmes, North Dakota[/pin] [/map]

A surface trough moving across the region associated with an upper level wave was the focus for severe weather across the region last Saturday. Plenty of instability was in place – MLCAPEs in the order of over 2000J/kg and sufficient shear (around 40 knots) was enough to support supercells in the region under the northwest flow. The first supercell in the region fired on the Manitoba side of the border and brought very large hail the size of tennis balls and strong winds to Roseisle and surrounding communities, such as Miami, MB. As the supercell drifted towards the south southeast it crossed the border into North Dakota near Walhalla, and held together quite well. A damage survey conducted by NWS Grand Forks it was found that several weak tornadoes were spawned out this supercell before it encountered a cluster of thunderstorms and weakened. Later on in the day several other tornadic supercells fired along the surface trough to the south of the initial supercell that was in northern North Dakota and produced more tornadoes.

After conducting a damage survey of the area, NWS Grand Forks concluded that 19 tornadoes touched down on June 27th, 2015. (Source: NWS Grand Forks)

After it was all said and done, it was concluded that the strongest tornado of all, a cone tornado, was one that touched down near Grand Forks and was of EF-2 strength (winds between 177km/h and 217km/h). The other tornadoes reported were mostly of rope type and weaker; of EF-0 to EF-1 strength. Thankfully the NWS Grand Forks was quick on the warnings and did a good job alerting the public of a nearby tornado – no injuries or deaths were reported with any of the 19 tornadoes.

One of the rope tornadoes in ND observed near Pisek. (Source: Matt D)

In other weather news this week, the west Pacific has been quite active typhoon-wise as three tropical storms are currently active, and of those one is expected to strengthen significantly by the beginning of next week, possibly to super typhoon status.

Eastern Pacific Active Season Starts Early

June 14, 2015June 14, 2015 Matthieu Leave a comment

The Eastern Pacific hurricane season is off to a record breaking start this year as hurricane Blanca formed south of the Baja Peninsula last week and meandered north towards it. Blanca finally made landfall early this past week on the Baja Peninsula; this is the earliest in the season that a hurricane has ever made landfall on the peninsula since records began.

[map autofit=”1″ disable_scrollwheel=”1″] [pin tooltip=”Baja California Sur” description=”24.101633, -110.632324″]24.101633, -110.632324[/pin] [pin tooltip=”Tropical Disturbance Formation Area”]15.427206, -103.469238[/pin] [pin]Puerto Vallarta[/pin] [/map]

Hurricane Blanca initially struggled with too much shear tearing the storm apart while it was organizing about 1000km southeast of the Baja Peninsula, but as it slowly drifted north, the environment became more favourable for development. The storm quickly formed an eyewall and became a category four hurricane. After an eyewall replacement and cooler waters churned up from the stormy seas, Blanca weakened to a category one. However, not too long after, it restrengthened to a category four. By the time the hurricane approached the Baja Peninsula it had encountered cooler waters and slowly weakened to a tropical storm.

Hurricane Blanca with a well defined eye on June 3rd. (Source: NOAA)

Although the storm was only classified as a tropical storm when it made landfall, bringing winds of 75km/h, the outages it caused were fairly significant. It caused 105,000 of the peninsula to lose power, and brought storm surges of about 5m to areas near the resort town of Puerto Vallarta, on the eastern shores of Mexico. In addition to that, the storm brought significant rainfall in the order of 75-150mm across the Baja Peninsula. A few days ago, the storm transitioned into a depression over the southwest US and produced some rains over the drought-stricken state of California.

Yet another storm has formed this past week southwest of the Baja Peninsula – hurricane Carlos. Although this one did not strengthen to a category four like Blanca did, there is a chance that it brings another significant rainfall to the Baja Peninsula as a tropical storm by mid-week next week. The storm season for the East Pacific officially starts May 15th.

India Faced with Intense Heat Wave

May 30, 2015May 30, 2015 Matthieu Leave a comment

A heat wave has taken hold across much of India in the past few weeks and will continue to do so before monsoon season arrives next week.

[map autofit=”1″ disable_scrollwheel=”1″] [pin]Bhubneshwar[/pin] [pin]Andhra Pradesh[/pin] [pin]Rajasthan[/pin] [/map]

A weak ridge aloft has allowed extreme heat to build into the region while tropical dewpoints over 25°C remain in place. With these temperatures and dewpoints combined, several locations in Eastern India, like Bhubneshwar, have seen humidex values above 55°C – signifying heat stroke is probable with any time spent outside. Not only that, but overnight lows stayed well above 30°C for several days in some regions, providing no relief to the residents. Additionaly, dust storms have been taking place across the drought stricken areas in the north. In Rajasthan, a dust storm killed seven people two weeks ago. Heat waves can be crushing to developing countries, such as India, resulting in exponentially more deaths and damages compared to first world countries as residents have limited access to clean drinking water to hydrate themselves, never mind air conditioned houses.

Asphalt was literally melting away on New Delhi roads due to high temperatures this week. (Source: Rappler)

Over half of the deaths (1,334 deaths) associated with the heatwave came from the Andhra Pradesh province, while the most recent overall death tally reached 1,826 people. This, according to Jeff Masters of Weather Underground, is the fifth deadliest heat wave in world history since record keeping began and second deadliest to India (deadliest was 1998). Water shortages were the main problem leading to dehydration and heat stroke; to combat this, the country brought in water tankers and aid to over 4,000 towns in the hardest hit areas.

Help might be on the way however. The seasonal rains that India experiences, called monsoonal rains, are advancing northwestward towards the heat-stricken provinces. These will not only bring much needed moisture to the region, but also allow temperatures to drop well below what India has been experiencing past few weeks. The few weeks preceding the monsoonal season typically do bring heat waves and dry weather to India, but some years are harsher and last longer than others.

Unsettled and Cooler towards Week’s End

May 27, 2015May 28, 2015 Matthieu Leave a comment

The warm and sunny weather we will be experiencing today will give way to showers on Thursday and cooler conditions on Friday after a cold front’s passage on Thursday night.

Wednesday

23°C / 12°C

Mainly sunny.

Today will be the nicest day in the second half of this week. Temperatures in the mid-twenties coupled with mainly sunny conditions and fairly light winds during the day will make it feel like a pleasant summer day. Cloud cover is expected to move in overnight – before Thursday morning – ahead of an approaching low pressure system which should keep the overnight low temperatures fairly warm in the low teens.

Thursday

19°C / 6°C

Showers possible during the day.

On Thursday a weak low pressure system passing to our south is expected to bring rain to a good part of Southern Manitoba during the morning and afternoon. Accumulations aren’t expected to come close to what we saw during the May Long Weekend storm, but areas near the border could see a decent rainfall. Winnipeg can expect to see totals between 2-5mm, while some areas near the border could see higher amounts – closer to 10mm. Some cloud cover will likely hang around through part the overnight period until the cold front passage.

Friday

12°C / 0°C

Cooler.

After the passage of the cold front overnight Thursday, cooler air will be ushered in on Friday. With highs only reaching the mid-teens, Friday is expected to be the coolest day of the week. Winds will also be quite gusty behind the cold front on Friday as strong cold air advection occurs behind the front. In turn, Friday night looks to be quite chilly with temperatures in the single digits. It’s too far out to know if temperatures will reach the freezing mark, but gardeners should be aware that temperatures might get close to 0°C.

Long Range

At this point models show that the weekend will be a nice one, high temperatures will be on an upswing as they gradually increase from Friday to Saturday and Saturday to Sunday. No precipitation is expected either, so it should be a good weekend to get out and enjoy the outdoors!

A Weather Moment

Author: Matthieu