GOES-14 in SRSO-R Scanning

May 18th, 2015

GOES-14 0.62 µm visible imagery [click to play animation]

GOES-14 0.62 µm visible imagery [click to play animation]

GOES-14 is producing imagery at 1-minute intervals as part of Super-Rapid Scan Operations for GOES-R (SRSO-R). Sectors that are scanned change each day and are determined by likely weather events. The animation above, in the southwest corner of the Monday May 18 sector shows strong convection over northern Louisiana. (A similar animation in mp4 format is available here (YouTube)) A benefit of 1-minute imagery is that it can capture the entire lifecycle of overshooting tops, cloud-top features that typically form and decay in less than 10 minutes.

GOES-R is scheduled to launch in March 2016. It will have the capability to provide routine 1-minute imagery over mesoscale-sized domains such as those sampled in the next three weeks by GOES-14. Real-time GOES-14 SRSO imagery is available through the SSEC RealEarth web map server and the GOES-14 SRSOR Imagery site.

Rapid Scan Operations allow the eye to distinguish between upper- and lower-level clouds that typically move at different speeds or in different directions. In the animation below (similar mp4 available here), high clouds over western Pennsylvania are moving over dissipating river fog in the central part of the state. Upper level clouds over southern New York are moving southward; low clouds are moving westward behind a back-door cold front: winds at White Plains, Newark, Trenton (and other stations) have all switched to easterly.

GOES-14 0.62 µm visible imagery [click to play animation]

GOES-14 0.62 µm visible imagery [click to play animation]

Another feature of interest was a thin layer of lake fog that was streaming northward across Lake Michigan during the morning hours, as seen in the animation below (also available as an mp4 movie file). Note the appearance of an undular bore propagating southeastward through the northern portion of the fog at the end of the animation; this may have been caused by an internal reflection of the strong southerly flow impinging upon the rugged southern coastline of the Upper Peninsula of Michigan. According to buoy data and the Terra MODIS Sea Surface Temperature product, Lake Michigan waters were still in the upper 30s to low 40s F — it was the pre-cold-frontal southerly flow of much warmer air with dew point values in the 50s and 60s F that led to the formation of the lake fog.

GOES-14 0.62 um visible channel images (click to play animation)

GOES-14 0.62 um visible channel images [click to play animation]

Rounds of deep convection persisted over parts of the Gulf Coast states during the day, which can be seen in the sunrise-to-sunset animation of GOES-14 visible images below (also available as an MP4 movie file). In Louisiana, some of these storms produced heavy rainfall and flash flooding, with a few water rescues necessary.

GOES-14 0.62 µm visible channel images (click to play YouTube animation)

GOES-14 0.62 µm visible channel images (click to play YouTube animation)

Ice motion in the Chukchi Sea

December 9th, 2014
Suomi NPP VIIRS 0.7 µm Day/Night Band images (click to play animation)

Suomi NPP VIIRS 0.7 µm Day/Night Band images (click to play animation)

AWIPS II images of Suomi NPP VIIRS 0.7 µm Day/Night Band data covering the 05 December – 09 December 2014 period (above; click image to play animation; also available as an MP4 movie file) revealed a fairly abrupt increase in the southwesterly motion of drift ice in the Chukchi Sea (off the northwest coast of Alaska), with giant ice floes beginning to break away north of Barrow (station identifier PABR) on 08 December. Although the northern half of the satellite scene saw little to no sunlight during this time, abundant illumination from the Moon (in the Waning Gibbous phase, at 82% of full) helped to demonstrate the “visible image at night” capability of the VIIRS Day/Night Band.

This change in ice motion was caused by an increase in northeasterly wind over that region, in response to a tightening pressure gradient between a 1040 hPa high pressure centered north of Siberia and a 958 hPa low pressure centered south of Kodiak Island in the Gulf of Alaska (below). The strong winds were also creating the potential for heavy freezing spray over the open waters north and south of the Bering Strait.

Suomi NPP VIIRS 0.7 µm Day/Night Band image, with surface analysis

Suomi NPP VIIRS 0.7 µm Day/Night Band image, with surface analysis

Along the northwest coast of Alaska, northeasterly winds at Point Hope (station identifier PAPO) gusted as high as 62 knots or 71 mph on 09 December (below). Not far to the north at Cape Lisburne (PALU), the peak wind gust was 39 knots or 45 mph.

Point Hope, Alaska meteorogram

Point Hope, Alaska meteorogram

Intense mid-latitude cyclone in the North Atlantic Ocean

October 13th, 2014
GOES-13 6.5 µm water vapor channel images (click to play animation)

GOES-13 6.5 µm water vapor channel images (click to play animation)

A large mid-latitude cyclone exhibited explosive development over the North Atlantic Ocean (south of Greenland) on 13 October 2014. This storm produced hurricane-force winds, according to surface analyses from the Ocean Prediction Center. GOES-13 6.5 µm water vapor channel images (above; click image to play animation; also available as an MP4 movie file) showed the intrusion of very dry air (yellow to orange color enhancement) associated with the approach of a potential vorticity anomaly early in the day, followed by the the cyclone wrapping up after it reached the occluded phase during the afternoon hours.

GOES-13 0.63 µm visible channel images (below; click image to play animation) revealed the very pronounced signature of cold air advection from the western to the southern quadrants of the storm, in the form of open-cell and closed-cell convective clouds.

GOES-13 0.63 µm visible channel images (click to play animation)

GOES-13 0.63 µm visible channel images (click to play animation)

Fog over Lake Superior

July 21st, 2014
GOES-13 0.63 µm visible channel images (click to play animation)

GOES-13 0.63 µm visible channel images (click to play animation)

The southerly flow of warm, moist air over the still-cold waters of Lake Superior on 21 July 2014 led to the formation of some interesting lake fog patterns, as seen in McIDAS images of GOES-13 0.63 µm visible channel data (above; click image to play animation; also available as an MP4 movie file). The images above are shown in their native GOES-13 satellite projection.

A similar animation of AWIPS images of re-mapped GOES-13 visible channel data with overlays of METAR surface reports and buoy reports (below; click image to play animation) showed that three of the northern Lake Superior buoys were reporting a water temperature of 38 to 39º F. As far north as Thunder Bay, Ontario (CYQT), air temperatures exceeded 90º F and the dew point exceeded 70º F.

GOES-13 0.63 µm visible images, with METAR and Buoy reports (click to play animation)

GOES-13 0.63 µm visible images, with METAR and Buoy reports (click to play animation)

A Terra MODIS Sea Surface Temperature (SST) product at 17:37 UTC (below) revealed that parts of the western half of Lake Superior exhibited SST values in the 40s F (cyan to blue color enhancement).

Terra MODIS Sea Surface Temperature product

Terra MODIS Sea Surface Temperature product

During the overnight hours preceding the images shown above, a Suomi NPP VIIRS IR brightness temperature difference “fog/stratus product” image at 07:43 UTC (below) showed a signal of widespread fog/stratus (yellow to red color enhancement) across much of the eastern half of Lake Superior.

Suomi NPP VIIRS IR brightness temperature difference

Suomi NPP VIIRS IR brightness temperature difference “fog/stratus product”