Category: Posts EN

Heat Wave for the Ages Affecting Normally Mild Alaska

Written by Team Morecast

 

The Fourth of July is traditionally known as a warm weather holiday across much of the United States. For many it represents the beginning of the summer. Residents of Alaska usually enjoy relatively cool temps during the traditional fireworks shows. But this past Thursday was not only the hottest Independence Day on record for the northernmost state in the union. Several stations reported their warmest temperatures for any day ever!

 

 

The average high for early July in Anchorage, the largest city in Alaska, is in the mid-60s deg F (upper teens deg C). Located on the shores of the always-chilly Gulf of Alaska, it’s a rare summer day that approaches 80 deg (27 deg C), and the all-time record high for any day was 85 deg F (29.4 deg C). That is, until Thursday. The official high reached 90 deg F (32 deg C) in Anchorage, with several other stations across the southern part of the state setting new all-time high marks (see map above, courtesy of the National Weather Service).

 

A strong, persistent ridge of high pressure is responsible for the hot weather. Alaska has been well above normal for close to two months now. Average temps in June ran five degrees above normal. The hot pattern is expected to continue for the next several days; Anchorage was only spared another record-shattering high temperature on Friday by the cover provided by wildfire smoke descending on the city. More records are likely to fall through early next week.

Major Hurricane Barbara Spins Across the Eastern Pacific; Atlantic Basin Still Quiet

Written by Team Morecast

 

Residents along the Pacific and Atlantic coasts enjoyed a very quiet beginning to the 2019 hurricane season. June, the first month of the official hurricane season, is typically quiet anyway. However, this will be the first year since 2009 featuring no storm activity in the first five weeks of the season. It’s a different story in the eastern Pacific, though.

A tropical depression developed on Sunday over the open waters of the eastern Pacific and was named Barbara by the afternoon. Barbara has steadily gained strength and is now a major hurricane, producing sustained winds to 130 mph ( kph). That’s a potentially very dangerous storm. Fortunately Barbara is not projected to affect any land masses. The storm will continue to move west and northwest, eventually dissipating late this weekend into early next week.

 

 

No tropical activity has been detected in the Atlantic basin since Subtropical Storm Andrea’s brief existence in May. The ENSO (El Nino – Southern Oscillation) remains in the positive mode (see graphic above). In other words, warmer-than-normal water temperatures over the western Pacific are resulting in stronger winds aloft. These winds act to disrupt developing tropical cyclones over the Atlantic basin. However, the ENSO is only weakly positive, and is forecast to remain that way. In addition, water temperatures are quite warm (see map below), which could provide fuel for cyclones later in the season.

 

Windy Storms Roll Across Portions of the Plains, Potentially a Derecho Pattern

Written by Team Morecast

 

Heat and humidity lingering into the evening hours on Thursday over the Central Plains provided plenty of fuel for severe storms. These storms became a long-lived squall line that has produced damaging winds from Nebraska and Kansas to Illinois.

 

 

 

“Derecho” is the name given to a squall line that produces 60 mph (100 kph) winds continuously for a period of at least six hours. Meteorologists typically observe a handful every year, mainly during the summer. The radar signature of the mature derecho is known as a “bow” for its resemblance to the standard archery equipment (see radar imagery above). Some of the most destructive severe weather episodes in the U.S. have been derechos. The derecho that slammed the Midwest and Mid-Atlantic in July 2012 cost nearly $3 billion in damages!

 

 

The current squall line easily qualifies as a derecho in terms of wind damage reports and duration (see map above). The squall line spun together on Thursday evening along the western Kansas-Nebraska border. Within the first hour or two it was producing wind gusts commonly in the 80-100 mph (130-160 kph) range. Numerous trees were uprooted and power poles were snapped like twigs. As the night wore on, the derecho lost some energy, but was still producing sporadic reports of damage with gusts 60-70 mph (100-115 kph). These continued through the morning hours. As of Friday mid-afternoon, the line was still tracking through southern Illinois with a damaging wind potential headed for portions of Kentucky and Tennessee. The environment remains favorable for additional squall lines to develop tonight in the Plains and Midwest.

Delayed Monsoon Intensifies Indian Heat Wave & Water Crisis

Written by Team Morecast

 

After a brief reprieve, more hot, dry weather is building across parts of central and northwest India. This new heat wave will only exacerbate severe drought conditions and water shortages. Some cities are being forced to truck water in from other locales due to water reservoirs being nearly bone-dry, a tremendously expensive operation.

 

 

Cyclone Vayu clipped the western part of India last week. Fortunately, the coast was spared the worst winds and surge flooding. Parts of the country even received welcome rain and cooler temperatures. However, the cyclone also sapped the developing monsoon trough of moisture and energy. The result is an already-delayed monsoon stalling in the far southern and eastern portions of the country. As of 20-June, only about 10-15% of the country has seen the onset of the monsoon, compared to two-thirds normally by this time (see map above). While the monsoon is beginning to creep northwesterly again, it will be several weeks yet before it reaches the west and northwest regions. For a largely agrarian country that receives 70% of its rainfall from the monsoon, the delay is devastating.

 

 

 

The delay may be partially due to the ingoing El Nino, a pattern of warming waters in the Pacific that has global impacts on weather. However, scientists also fear a weaker and more unpredictable monsoon due to climate change. Some regions have seen successive weak monsoons, combined with human-driven factors, result in severely depleted water supplies. Chennai, the sixth-largest city in India, home to more than 4.5 million people, is one such city. Officials there have had to employ 400 tanker trucks to deliver thousands of cubic feet of water to local reservoirs which are otherwise spent. But a nation-wide monsoonal delay reduces the ability of neighboring regions to help, creating a crisis everywhere.