Tornado near Sheridan California 1/9/2017

Monday’s storm system managed to generate a mini-supercell northeast of Sacramento, Ca. This is the first tornado of the year in California.
Fox 40 from Sacramento reported on it in this video…

The National Weather Service issued a storm report and called this a funnel cloud. But the rotating winds are clearly extending to the ground, making it a tornado.

The Base Reflectivity and Storm Relative Velocity are shown from 2:00 pm Monday, January 9. The Reflectivity shows hints of a supercell, including a rear flank downdraft wrapping into the storm. The Storm Relative Velocity at the same time indicates rotation in the updraft above the ground. These are signs to the warning forecaster the storm could produce a tornado.

Although a brief tornado was produced, there were no reports of any damage as this occurred in an open field.

Jim Purpura, CCM

Base Reflectivity of Tornadic Storm near Sheridan, CA
Storm Relative Velocity image of Tornadic Storm near Sheridan, CA

James Purpura CCM of WeatherExtreme Ltd. presentation at the AMS Meeting

January 26, 2017 – Meteorologist James K. Purpura, CCM, of WeatherExtreme Ltd., will be presenting at the American Meteorological Society(AMS) Conference held in Incline Village, Nevada. Along with Y. E. Kachiwanda and R. Jubach, they will be presenting “Malawi Weather Chasers: Using Social Media to Jumpstart Dissemination, Event Reporting, and Preparedness”. Jim was in South Africa at the end of 2015 with the SARFFG-SWFDP to promote weather safety in South Africa. A Flash Flood Warning System was expanded to a severe weather warning system in South Africa and 8 of its neighboring nations in the region. Their presentation will discuss that in conjunction with WhatsApp, a social media tool, they have been able to develop a weather spotter network, as well as communicate forecasts, warnings, observations and storm reports to remote villages, Disaster Risk Managers, media, and local, regional, and national government officials.

For additional presentation information, click here

For James K. Purpura’s full bio, click here

…Large summer heat wave expands across the Midwest…

Chicago graphic

Photo Credit:NOAA/NWS

A growing dome of warm air will be expanding from the Great Plains into the Midwest. Excessive Heat Watches (dark brown on the map) or Heat Warnings (purple) are in effect across a large area from Illinois, to Minnesota and North Dakota, then south to Kansas.
WWA Map 7-19-16

Photo Credit:NOAA/NWS

People in different areas of the country acclimatize to heat events in different ways. What is common to heat related deaths or heat related injuries (heat exhaustion or heat stroke) is a lack of adjustment to the heat, along with dehydration and inadequate cooling. In places where summer air conditioning is not commonly used, those in poor health and the elderly can be most at risk.

Within the City of Chicago, where 739 deaths occurred over 5 days in 1995, many of these deaths occurred in homes where seniors lived without air conditioning or other adequate cooling, and where concern over crime made them reluctant to open windows. See the warning information posted by the NWS Chicago on this upcoming event.

Chicago graphic

Photo Credit:NOAA/NWS

Long range models indicate the heat will retreat from the Midwest to the southwestern US as we begin next week, with the heat likely affecting Nevada and California.

El Niño Induced Storms finally hit California

El Niño, a warming of the waters in the central and eastern equatorial Pacific, is associated with a variety of weather patterns. One such pattern, a strong southern jet stream, brought a series of storms to drought-stricken California in early January. The jet stream took a dip to the south and a series of storms brought high winds, heavy rain, flooding, mountain snow and even a couple of tornado warnings. The effects from this El Niño have been anticipated in California for at least six months, with the hope being that it could be a “drought buster.’ Whether it will be or not won’t be known until spring, but if this week’s storms are any indication California’s water problems may ease a bit this year.



This El Niño got its official start in the late spring, when the rainy season is usually over in California, but a couple of late season storms in the southern part of the state were followed by the rainiest summer on record in San Diego and Los Angeles. This didn’t do much to lessen the drought conditions, but it did give hope that there might be more to come. “Traditional” El Niño storms ride in on a strong southern branch of the jet stream, rapidly bringing storm after storm into the state on the jet streams 100+ mile per hour winds.

The fall and early winter did not have this synoptic setup, so the storms that hit California were not what people typically think of as El Niño storms, but nevertheless they were good rainfall producers with decent snowfall totals in the mountains. On December 30, when the winter’s first manual snowpack survey was taken, the results were that for the state as a whole the water content of the snowpack was 105% of normal. While not terribly impressive, this was more than twice what the previous year’s survey found at the same time of year. More recent data from the automated SNOTEL sites shows the snowpack in all of the reporting basins (Northern Great Basin, Truckee River, Lake Tahoe, Carson River, Walker River and Klamath) reporting above average snowpack for the date.

Another set of drought indicators are the Northern Sierra “8 Station Index” (8SI) and the San Joaquin “5 Station Index” (5SI) that are calculated from the cumulative rainfall at chosen sites in the Sierra Nevada. These indexes are use determine the water allocations for central valley farmers. The 8SI is about 96% of normal to date, but is actually well behind the value from last year at this time; while the 5SI is about 125% of normal. The difference is not too surprising since the 5SI sites are farther south and El Niño precipitation favors the southern portion of the state.

While it is far too early to tell whether or not this year’s strong El Niño will be a “drought buster”, it does appear that it’s off to a good start in terms of water supply, Californians are just keeping their fingers crossed that along with the much needed water, El Niño does also bring with it too much destruction.

Nor’easter Brings Heavy Rain and Strong Winds to Northeastern United States

A coastal low pressure storm system known as a Nor’easter has been impacting New England since Wednesday, bringing gale force winds (39-54 mph), heavy rain and coastal flooding, and power outages across the region.

Visible satellite image of Nor’easter on October 23rd, 2014 at 9:30a.m. EDT (NOAA)

Nor’easters are characterized by their strong northeasterly winds blowing over coastal areas, and usually develop where warm air from the Gulf of Mexico collides with cold arctic air from Canada. Although these storms can occur at any time of the year, they are typically the strongest and most frequent between September and April.

Some areas of New England have received as much as six inches of rain from this storm system, which may actually be welcomed, as the region has been experiencing abnormally dry to moderate drought conditions, according to the U.S. Drought Monitor.

U.S. Drought Monitor indicating the Northeastern U.S. is under abnormally dry to moderate drought conditions.

Kayla Jordan