Elsewhere in Weather News: November 30th, 2013

Cyclone Lehar Hits India

This past week a weak cyclone hit India’s east coast as a weak cyclone depression. The cyclone – Cyclone Lehar was classified as a severe cyclone in the Bay of Bengal with winds over 100km/h but has since been downgraded. Unfavorable sea surface temperatures and shear for storm development did a good job on tearing up the storm apart before landfall. The storm made landfall as a tropical depression on Thursday, with winds of 60-70km/h at landfall. Evacuation precautions were taken by the India Meteorological Department because of the strength of the cyclone while it was over the Bay of Bengal but the only real threat that Lehar brought was flood threat. No significant damage was reported from the storm but some crops have been damaged and a few districts vulnerable to flooding in India’s Andhra Pradesh state have been affected by flooding.


Cyclone Lehar as it was struggling to organize over the Bay of Bengal. (Source: NDTV)
Cyclone Lehar as it was struggling to organize over the Bay of Bengal. (Source: NDTV)

Arctic air dominated over a good part of both Europe and the United States this week which brought minimal significant weather to the regions. Apart from significant snowfall associated with a trough of low pressure affecting the eastern seaboard of the United States earlier this week, active weather has been kept to a minimum. The next big weather event is likely to be a winter storm which will affect the northern states (MT, ND) and even southern Manitoba on Tuesday and Wednesday of next week.

Elsewhere in Weather News: October 12th, 2013

India Braces for Super Cyclone Phailin

An extremely powerful cyclone churning in the Bay of Bengal is targeting India’s east coast and is expected to make landfall this morning. This is one of the strongest cyclones India has seen in recent history and the strongest since 1999. Phailin has maintained category five status since Friday afternoon and is expected to only slightly weaken to a high end category four (as its eyewall moves over land) before making landfall. Conditions were primed for quick intensification on Thursday; SSTs approaching the 30°C mark and shear quite low. Phailin went from a tropical cyclone to category four on Thursday thanks to these ideal conditions for intensification. Already, India has evacuated tens of thousands of residents from low lying coastal areas but Phailin still has the potential to wreak much havoc on India. Already one death has been reported associated with a tree falling onto a house as of Friday night.

Phailin

Incredible image of Phailin just before it makes landfall; a well defined eyewall and very cold cloud tops are present showing that the storm is well-organized. (Source: CIMSS)

Storm surge will be a real problem with this cyclone – a forecasted 11 foot storm surge is expected to arrive as Phailin makes landfall near Brahmapur. The good news is that the coastline goes up in elevation fairly quickly as you move inland, therefore residents that should be most concerned with storm surge should be the ones that live near shorelines. With category five cyclones like this one winds as well as flooding problems are almost a given. In this case, winds will be sustained over 240km/h, gusting over 300km/h, and anywhere from 200mm to 350mm can be expected to fall around where Phailin makes landfall. The cyclone is expected to move inland and die off fairly quickly as it moves over land as opposed to being over warm ocean waters.

SST and shear

Sea surface temperatures, overlayed with shear. Note the low shear values (5-10 knots) and SSTs between 29°C and 30°C; sufficient to sustain category five storms. (Source: CIMSS)

Another storm; typhoon Nari is currently threatening Vietnam to make landfall at the beginning of next week. It is still recovering from its passage over the rugged islands of the Philippines but is expected to strengthen to a category three typhoon over the South China Sea before landfall. Models are suggesting yet another typhoon to spin up behind Nari but this one is expected to take a turn towards Japan. So, overall a very active weekend and upcoming week cyclone and typhoon-wise!

Elsewhere in Weather News: May 11th, 2013

Cyclone Duo in Indian Ocean

Two separate cyclones formed in the Indian Ocean this week and will continue to intensify and organize over the weekend. A low shear environment combined with warm sea surface temperatures of around 30°C, were key factors in the formation of these two cyclones.
The first cyclone, located south of the equator, is named Jamala. This cyclone is headed west and is only expected to intensify to a category one hurricane for a short amount of time before weakening to a tropical storm again. Despite reaching category one and heading west towards land, Jamala is not expected to affect Madagascar or any parts of eastern Africa as models show it weakening to almost nothing before reaching the coast.

The second cyclone, cyclone 01B located north of the equator, is more of a concern to Bangladesh and surrounding countries. This cyclone has the potential to cause substantial damage to Bangladesh as land is prone to flooding there. Storm surge will likely be an issue, depending on the strength of the hurricane when it makes landfall. As of Friday evening, 01B had estimated maximum surface winds near the 95km/h mark but was expected to increase in strength as it moved north, towards Bangladesh. Landfall is still a ways away, but its stronger outer bands are expected to arrive near the Myanmar and Bangladesh shores early Tuesday.

Cyclone 01B

Enhanced infrared image of tropical cyclone 01B Friday night. (Source: CIMSS/NHC)

The Indian Ocean cyclone season is most active from the beginning of spring to early winter but it is possible to have cyclones form throughout the year.

Elsewhere in Weather News: May 4th, 2013

Let it Snow!

Record-setting snowstorms were the topic of conversation in parts of the US this week.

Snowfall reports

Snowfall map until Thursday morning. (Source: NOAA)

Springtime weather was delayed once again as a significant trough moved across Central US dragging down unseasonably cold arctic air with it. Friday morning, temperatures at 850mb reached below freezing all the way down to Mexico; and snow fell from Northern Ontario all the way down to northern parts of Arkansas and Oklahoma! Many snowfall records were shattered, some of the most significant being:

  • Britt, Iowa – Achieved a snow depth of 28cm, beating the old record of 25cm (in 1947).
  • Chippewa-Falls/Eau Claire, Wisconsin – Recorded a snowfall of 22cm shattering the old record of 5cm (in 1946).
  • Extreme north-west Wisconsin – Recorded a snowfall of 46cm.

The trough will not make it to the East Coast as the main jet stream is retreating north and a cutoff low will form in southern US. This cutoff low is expected to slowly drift across the region feeding into tropical moisture while dropping significant rainfall over parts of the south-east and east-central US. Accumulations of over 80mm are expected, increasing concerns that flash floods might be a problem over the weekend.

In other news, a category one cyclone formed off the north-eastern coast of Australia, however it had minimal impacts on land as it fizzled out and only brought lowland flooding and erosion to coastal areas.

Italy also saw an active week with a large tornado reported in it’s northern region. An approaching shortwave combined with significant instability and sufficient shear on Friday was the cause for severe storms in the area.

Short video of the Italian tornado as seen from the nearby city of Castelfranco Emilia. (Source: R. Melotti)