Wednesday, March 22, 2017

A New Weather Eye in the Sky


GOES-16, atop a Atlas V booster, leaves the launch pad.
Credit: NOAA
Last fall members of the meteorological community anxiously awaited the launch of a new weather satellite, one that could revolutionize weather satellite science. Dubbed the GOES-R at that time the satellite was equipped with state-of-the-art imaging equipment and array of sensors. GOES-R was originally scheduled to launch on November 4, 2016. We collectively held our breath in early October when Hurricane Matthew clobbered eastern Florida as it moved north just off the coast. Hurricane Matthew had a close encounter with the Kennedy Space Center. The satellite was safely secured and escaped harm, but damage to Cape Canaveral and at the Kennedy Space Center forced the launch date to November 16. On November 3 the launch date was pushed to November 19 because of a minor issue with the Atlas V booster. Finally at 6:42 p.m. EST on November 19 the GOES-R was launched into space.

GOES-16
Credit: NOAA
On November 29 GOES-R reached geostationary orbit at an altitude of 22,000 miles and officially designated GOES-16. Testing and calibration of the satellite systems began at that point and is continuing. Though not yet officially operational (data is preliminary and undergoing validation), GOES-16 images and products seen so far are nothing short of spectacular.


Not only is GOES-16 monitoring our terrestrial weather, it is also monitoring space weather. There are sensors on board for observing solar flares (Ultraviolet and X-Ray Irradiance Sensors, the Solar Ultraviolet Imager (SUVI), monitoring the flux of charged particles associated with the Aurora Borealis (Environment In-Situ Suite (SEISS), and a new, faster magnetometer for monitoring the earth's magnetic field.

The cool stuff related to terrestrial weather includes the Geostationary Lightning Mapper (GLM), the first lightning detector in geostationary orbit. It monitors for lightning flashes in the Western Hemisphere, both in-cloud lightning strikes and cloud-to-ground strikes.

The Advanced Baseline Imager (ABI) is the primary imaging instrument on GOES-16. It will provide three times more spectral information, four times the spatial resolution, and more than five times faster temporal coverage than the current system. The increase of both speed and resolution will be a huge advantage to forecasters. Mesoscale (1000 x 1000 km) spatial resolution will be 2 kilometers, with updates as often as every 30 seconds. This will have a tremendous positive impact on the ability of forecasters to monitor and respond to developing weather situations.

You may have already seen images from GOES-16 on the web. The difference on visible images is astounding, like the difference between your old TV and the latest HD TV image. Here is one of those images.

Visible image from GOES-16 on the morning of March 7, 2017. This is one image captured from a loop.
Credit: CIRA/RAMMB at Colorado State University

This image is one from a loop of images assembled by the Cooperative Institute for Research in the Atmosphere (CIRA)/Regional and Mesoscale Modeling Branch at Colorado State University in Fort Collins. The amount of detail is amazing. These high resolution images from GOES-16 have even captured the smoke from small wildfires. For a full-size high resolution of this image and the image loop, click here.


NOAA emphasizes that "the GOES-16 satellite has not been declared operational and its data are preliminary and undergoing testing." The switch to operational status should occur this summer or in the fall.

If you would like to view the different types of GOES-16 satellite images there is a nice sampling of GOES-16 images and videos at this link.

Wednesday, March 1, 2017

Winter 2016-2017 Recap: The Winter that Mostly Wasn't

We put the wraps on climatological winter (December-February) yesterday, although winter weather is not out of the question in many parts of the country over the next two to four weeks. Climatological winter was capped off by very springlike weather, including a severe weather outbreak in the central U.S.

We can take a quick look at what winter has been like across the country using the latest map of the Accumulated Winter Season Severity Index. Most of the country has experienced a mild winter, with the only notable exception the northwestern U.S. and far northern New England. Omaha, NE and Des Moines, IA are on track for record mild winters. Note that the AWSSI continues to be accumulated until the last day with a maximum temperature of 32°F, the last day with measurable snow, or the last day with measurable snow on the ground. The factors that are keeping other locations from having record mild winters are snow early in the season and several periods of cold weather in December and January.

The Accumulated Winter Severity Index as of March 1, 2017.
The maps of the average temperature departure from normal for December through January depict very much the same pattern. Average temperatures for the period were above normal from the Plains to the east coast. Colder than normal temperatures occurred in the northwestern quarter of the country.


The map of maximum temperature departures mimics the mean temperature map, but the map of minimum temperature departures shows a larger area of warmer than normal temperatures, particularly in the southwestern U.S.



On a monthly basis it's clear that February was a huge contributor to the warmer than normal winter. Final numbers aren't all in yet, but many locations in the central and eastern U.S. will find that this February will be the warmest on record.

Click on map to see larger version

The precipitation map does not contain too many surprises. Precipitation in most of the western U.S. was much above normal. It was a much drier than normal winter in a bulls-eye in the central U.S. extending from northern Arkansas through Missouri and Illinois. It was also dry in the mid-Atlantic and Florida.



Snowfall during climatological winter was well above normal from the northern Plains to the Sierras, and near to above normal in much of New England. Snow season (July 1- June 30) is not yet over and many locations could yet see some substantial snowfall in the spring. There definitely has been a snow drought in much of the central U.S. Chicago did not have any snow cover in January or February for the first time in the 146 years.



CoCoRaHS observations were included in both the precipitation and snowfall maps.

Ice cover on the Great Lakes is only 10 percent of what it usually is on this date. The average coverage on March 1 is about 43 percent, and as of today it was 4.5 percent.


Ice cover on the Great Lakes as of 2/28/2017

The warm weather in February, especially the last ten days of the month, is particularly problematic for vegetation this spring. The warm weather coaxed trees and bushes to bud and plants to emerge from the soil much earlier than normal. The U.S. National Phenology Network data shows that "spring" is almost three weeks ahead of schedule as far north as the Ohio Valley. The risk of freezing weather is pretty much a sure thing for the next several weeks, and the possibility of damage to emerged vegetation is rather high.



Finally, the severe weather season got off to an early start in the Midwest yesterday with an outbreak of severe weather across the Midwest. Several strong tornadoes caused significant damage and several fatalities in Illinois, Missouri, and Indiana. The severe threat moved east today with severe weather from new York south through Alabama.