GOES-14 in SRSO-R Mode

August 10th, 2015

GOES-14 Visible (0.62 µm) Imagery  [click to play animation]

GOES-14 Visible (0.62 µm) Imagery [click to play animation]

GOES-14 is again in SRSO-R (Super Rapid Scan Operations for GOES-R) mode, affording the opportunity for 1-minute imagery over select regions of the United States. Information on the daily activity is available here; SRSO-R will continue through 21 August and serves as a reminder of the kind of routine scanning abilities that will be available when GOES-R is operational.

The images above, from the morning of 10 August, show a variety of features (thunderstorms over the Piedmont of South Carolina, North Carolina and Virginia, wave clouds over the high terrain of North Carolina, river valley fog in northern West Virginia and western Pennsylvania, fog in southern Vermont, etc.). High temporal resolution allows a better understanding of the cloud behavior.

As solar heating increased toward mid-day and the atmosphere became more unstable, clusters of convection developed over parts of the Great Lakes region as seen in the MP4 animation below. One of the thunderstorms (which developed in eastern Wisconsin ahead of an approaching cold front) produced 1.75-inch diameter hail, and a brief EF0 tornado (SPC storm reports); not far to the south, a thunderstorm wind gust of 44 mph and 1.10 inches of rainfall in 30 minutes occurred at Milwaukee International Airport (Local Storm Reports). The MP4 movie file is also available as a very large (197 Mbyte) animated GIF.

GOES-14 Visible (0.63 um) images [click to play animation]

GOES-14 Visible (0.63 um) images [click to play animation]

Over the Southeast US, widespread damaging wind reports resulted from strong thunderstorms forming ahead of a Mesoscale Convective Vortex that was moving southeastward across the Tennessee River Valley region (SPC Mesoscale Discussion). The GOES-14 visible images below vividly displayed the complex nature of the convection associated with this feature. The MP4 movie file is also available as a very large (87 Mbyte) animated GIF.

GOES-14 Visible (0.63 µm) images [click to play animation]

GOES-14 Visible (0.63 µm) images [click to play animation]

In the Northeast US, the GOES-14 visible images below showed convective development which was being aided by boundary layer convergence along a weak trough axis (surface analysis). 1.00-inch diameter hail was reported at Franklin in Upstate New York at 2035 UTC, and damaging winds were reported in Victor, New York at 2002 UTC and then again in Lyons, New York at 2129 UTC. The MP4 movie file is also available as a very large (59 Mbyte) animated GIF.

GOES-14 Visible (0.63 µm) images [click to play animation]

GOES-14 Visible (0.63 µm) images [click to play animation]

To access realtime GOES-14 1-minute data directly, click here or here.

One of the things SRSO-R supports is the 2015 Summer Experiment at the Aviation Weather Center. For more information on that experiment, click here.

Flooding Rains in Tampa

August 4th, 2015
MIMIC Total Precipitable Water [click to play animation]

MIMIC Total Precipitable Water [click to play animation]

After a July with rainfall that was significantly above normal (Link), Tampa experienced heavy rain on both August 1st and August 3rd, leading to flooding conditions. The animation of Total Precipitable Water, above, from 2-4 August, shows the moisture-rich environment in which the showers and thunderstorms developed. Tampa appears to be in a corridor of moisture transport between tropical easterlies over the Atlantic and more westerly motion in advance of a surface trough that had sagged into the northern Gulf of Mexico. As a result of the rains (3.89″ on 1 August and 4.39″ on 3 August), Flood Warnings and Flood Watches persist on 4 August, and River Gauges (Source: http://water.weather.gov/ahps/index.php) continue to show conditions above flood stage (below).

River Gauge Observations (Left) and National Weather Service (Tampa Bay) County Warning Area warnings (right) [click to enlarge]

River Gauge Observations (Left) and National Weather Service (Tampa Bay) County Warning Area warnings (right) [click to enlarge]

GOES-13 Imagery, below, captured the evolution of the heavy rains on 1 August (Loop available here as mp4). These rains fell mostly during the day, and satellite data suggests training convection (that is, repeated development of thunderstorms over one region) produced the rain.

GOES-13 10.7 µm infrared imagery [click to play animation]

GOES-13 10.7 µm infrared imagery [click to play animation]

GOES-13 0.63 µm visible imagery [click to play animation]

GOES-13 0.63 µm visible imagery [click to play animation]

Visible imagery (Click here for mp4) during the day on 1 August (above) confirm the training nature of the convection over Tampa.

In contrast, the heavy rains early on 3 August were associated with a strong mesoscale convective system (loop shown below, or available here as mp4) that developed over the northeast Gulf of Mexico and then sagged southward over Tampa.

GOES-13 10.7 µm infrared imagery [click to play animation]

GOES-13 10.7 µm infrared imagery [click to play animation]

The toggle below of 11.45 µm Brightness Temperature and Day Night band visible (0.70 µm) imagery from 0751 UTC on 3 August shows very cold overshooting tops with temperatures as cold as -88 C over the northwest Gulf. Transverse banding around the periphery of the system is also apparent. Such bands are a signal of turbulence (although no reports were issued at that time).

Suomi NPP VIIRS Infrared Imagery (11.45 µm) and Day Night Band Visible (0.70 µm) Imagery, 0751 UTC 3 August 2015 [click to enlarge]

Suomi NPP VIIRS Infrared Imagery (11.45 µm) and Day Night Band Visible (0.70 µm) Imagery, 0751 UTC 3 August 2015 [click to enlarge]

How much rain has fallen in the week ending 4 August 2015? The image below, from this site, shows totals exceeding 10″ just north of Tampa.

Weekly Rain Totals over Florida [click to enlarge]

Weekly Rain Totals over Florida [click to enlarge]

The long-lasting remnants of Tropical Storm Bill

June 21st, 2015
Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images (click to enlarge)

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images (click to enlarge)

Advisories on Tropical Storm Bill were initiated when the system organized and intensified off the coast of Texas at 03 UTC on 16 June 2015 (GOES-13 IR image animation). Bill moved inland during the afternoon hours on 16 June, as can be seen in a comparison of Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images at 1916 UTC (above).

Late in the day on 17 June, the general appearance of downgraded Tropical Depression Bill on GOES-13 6.5 µm water vapor channel imagery (below) began to suggest that the system might be undergoing an extratropical transition (intrusion of dry air in the southern quadrant, along with a blosominig comma head signature on the northern quadrant) — but Bill maintained sufficient tropical characteristics to continue being named a tropical depression.

GOES-13 6.5 µm water vapor channel images, with surface pressure and frontal analyses (click to play animation)

GOES-13 6.5 µm water vapor channel images, with surface pressure and frontal analyses (click to play animation)

The circulation of TD Bill maintained its identity on satellite imagery as the storm remained over land for the next 3+ days, curving northeastward and moving across the Ohio River Valley region. Slow-moving TD Bill dropped over 12 inches of rain at some locations in Texas and Oklahoma, with amounts exceeding 8 inches in Missouri and 6 inches in Indiana (WPC storm total rainfall totals), before being designated a post-tropical feature at 21 UTC on 20 June (WPC advisories).

GOES-13 10.7 µm IR channel images (click to play animation)

GOES-13 10.7 µm IR channel images (click to play animation)

The history of Bill can be followed in a multi-day animation of GOES-13 10.7 µm IR channel imagery (above); in addition, the lower-tropospheric circulation of Bill can be followed using the CIMSS 850 hPa relative vorticity product (below).

GOES-13 850 hPa relative vorticity product (click to play animation)

GOES-13 850 hPa relative vorticity product (click to play animation)

As the post-tropical remnants of Bill emerged over the Atlantic Ocean early in the day on 21 June, it still appeared to be associated with an arc of deep convection as seen on a comparison of Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images at 1742 UTC (below). A similar comparison of Terra MODIS visible and IR images at 1514 UTC can be seen here.

Soumi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

Soumi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

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)