Prescribed burns lit up GOES-16 imagery on April 11 in the eastern half of Kansas. The 2 km 3.9 um IR channel shows an abundance of hotspots across the region during the day. The 0.5 km 0.64 um visible channel reveals widespread smoke. Ozone alerts were issued for parts of Kansas given the increased particulate matter in the air.
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
During the overnight hours of March 19-20, 2017, an amplifying upper level shortwave moved off the Mid Atlantic coast and led to the rapid development of a mesoscale oceanic cyclone across the Gulf Stream east and southeast of Cape Hatteras. The upper level feature moved south and southeast along the backside of a deep upper level long wave trough near 68W. The global models including the GFS and ECMWF were not well initialized with the upper level shortwave and consistently, over the previous several model runs, were only indicating a weak trough would develop at the surface. Conversely, the 4km NAM and HRRR were each showing surface low development and significantly higher associated surface winds than shown by the coarser global models. OPC forecasters had been carrying storm warnings across a few offshore zones through 00 UTC March 20, 2017.
Animation of the 20 March 2017 00 UTC 4 km NAM pmsl and surface winds. Yellow boundaries delineate the OPC offshore forecast zones. Click here to open in a new window.
The GOES-16 water vapor imagery, including the 6.9 um mid-level and 6.2 um upper-level, suggested that the mid/upper shortwave was more amplified than initialized by the global models. The feature was also apparent in the GOES-16 7.3 um lower-level water vapor imagery, indicating it may be vertically stacked or at least extend through the lower levels. The three water vapor channels alone indicated there was likely adequate forcing through the upper and mid levels, and even into the lower levels, to support the development of a surface low. However, the low level circulation analyzed in the GOES-16 3.9 um shortwave infrared imagery confirmed the presence of the surface low. In addition, the enhanced baroclinicity the system encountered as it tracked across the Gulf Stream likely played a big role in the storm’s intensification. The sea surface temperature (SST) gradient along the north wall of the Gulf Stream can be seen in the GOES-16 3.9 um shortwave infrared animation.
GOES-16 6.2 um upper-level water vapor animation valid 2102 UTC 19 March 2017 – 0902 UTC 20 March 2017. *Preliminary, Non-Operational Data* Click here to open in a new window.
GOES-16 6.9 um mid-level water vapor animation valid 2102 UTC 19 March 2017 – 0902 UTC 20 March 2017. *Preliminary, Non-Operational Data* Click here to open in a new window.
GOES-16 7.3 um lower-level water vapor animation valid 2102 UTC 19 March 2017 – 0902 UTC 20 March 2017. *Preliminary, Non-Operational Data* Click here to open in a new window.
GOES-16 3.9 um shortwave infrared animation valid 2102 UTC 19 March 2017 – 0902 UTC 20 March 2017. *Preliminary, Non-Operational Data* Click here to open in a new window.
Upon reviewing the GOES-16 imagery and evaluating the most recent model guidance, the overnight OPC forecaster extended the storm warning through the night period, and also expanded the warning to include the outer mid Atlantic offshore waters. The significantly improved temporal and spatial resolution of the GOES-16 imagery, along with the additional water vapor channels, allowed forecasters to better diagnose the strength of the upper level shortwave and also, the presence of the surface low, which then gave forecasters more confidence in amending the warnings. Even as the both the upper level feature and the surface low appear to shear and weaken in the three GOES-16 water vapor channels and 3.9 um shortwave infrared band around 06 UTC, there was a ship which reported gale force winds (35 kt) at 06 UTC well southwest of the surface low.
Thanks for reading!
James Clark (OPC) and Michael Folmer (CICS)
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
Building on the blog post by Bill Line on 03/30/17, Paul Iniguez (SOO-Phoenix WFO) put together the following case study on the synoptic scale dust event that affected much of the Southwestern U.S., most notably, the Mojave Desert.
A strong upper level low quickly moved into the Southwest U.S. on Thursday 30 March 2017. The rapid airmass change brought about very strong winds across the region, as depicted above. Most of the significant impacts were in the Mojave Desert, including wind gusts up to 80 mph, power outages, and a few tipped semis. [LINK] Dust was very widespread with this event, with very low visibility reported. [LINK]
GOES-16 0.64 um “Red” Visible animation of the dust event on 03/30/17. Created in AWIPS-II *Preliminary, Non-Operational Data*Click here to open in a new window.
With the new GOES-16 data, we were able to see several phenomena that were not previously detectable with GOES-15. To begin with, here is an eight hour loop of GOES-16 Ch 2 (red visible). Some interesting things to note in the data. Watch the numerous dry lake beds/playas become “activated” as the winds pick up ahead of the incoming front. Watch the initial wall of dust form as it moves south through the Mojave, and a second wall form in the far southern edge of the Mojave that moves into the Sonoran Desert toward sunset.
Looking closer, this second loop over Imperial County, CA shows several benefits of the GOES-16 data over the GOES-15. Note that this loop does not account for the typical latency of GOES-16.
First, we see the obvious improvement in resolution, 0.5 km vs 1 km. Because of this, and the increased sensitivity of the instrument (higher bit rate, meaning it can resolve finer features), GOES-16 is capturing a lot of blowing dust moving out across the Salton Sea that GOES-15 simply doesn’t see. It is only much later, around 2330Z, that GOES-15 finally picks up a more substantial plume. With the GOES-16, we can also see blowing dust coming off the agricultural fields north of the sea moving to the southeast. Finally, perhaps because of the increased sensitivity and difference in position of the satellites, the GOES-16 data is usable for much longer. GOES-16 is returning useful data to 02Z and thus captures the incoming second wall of dust.
Of course the dust lasted beyond sunset. The GOES-16 Legacy IR (Ch 14) was able to better discern the boundary, again likely due to improved resolution and increased sensitivity, compared to GOES-15. In fact, with GOES-16, you can arguably get better a sense of optical depth, perhaps useful in figuring out where the worst dust is. With further research, perhaps we’ll be able to get a sense of dust density (thus visibility). Of course this is only useful if the surface features are not obscured by higher clouds, which here could be separated out by their brighter appearance.
Thanks for reading!
Paul Iniguez (SOO – Phoenix WFO) and Michael Folmer (CICS)
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
A significant severe weather event impacted E TX, LA, and MS on Sunday, April 2. A SPC Moderate Risk for severe had a region upgraded to High at the 1630 UTC Day 1 outlook for the tornado threat. Given the threat, GOES-East RSO was requested by SRH, and Mesoscale Domain Sector 1 granted over the region. The early day setup included a closed upper low moving NE across central Texas towards Arkansas. At the surface, an MCS and associated cold pool from the previous evening was traversing eastward through Texas. Ahead of this feature, strong southerly flow drew up warm, moist Gulf air.
The evolution of the overnight MCS is depicted in 5-min GOES-16 ABI 10.4 um clean window IR imagery below. This channel is the “cleanest” of the IR channels because it is least sensitive to absorption by atmospheric constituents such as water vapor. The development of thunderstorms during the evening of the 1st is seen as rapid cooling of the cloud tops in SW Texas. The rapid expansion of the cold cloud tops signals the continued maintenance of convection, and development of an MCS. By early morning on the 2nd, rapid warming becomes evident, especially on the southern end of the MCS, signaling a weakening and dissipation of thunderstorm activity. The higher spatial (2km vs 4 km) and temporal (5-min vs 15-min over CONUS) resolution of the GOES-16 satellite allows for these cloud top temperature trends to be more easily and promptly diagnosed.
By late morning, convection began to develop within the warm sector in E Texas and Louisiana ahead of the previous evening’s weakening cluster of thunderstorms. These storms quickly became severe, producing large hail, wind and tornadoes. Detection of convective initiation is significantly improved in the 1-min, 0.5 km visible imagery, as was shown in a previous blog post that compared GOES-16 data with GOES-13 data for initial storm development.
Storm top features of mature convection are also easier to discern in the GOES-16 imagery compared to current GOES satellites. Below is a side-by-side comparison of 0.5 km, 1-min VIS from GOES-16 and 1 km, Rapid Scan (5-15 min) VIS from GOES-13. Additionally, GOES-16 2 km, 1-min IR is compared with GOES-13 4 km, Rapid Scan IR. The time period is 2145 UTC to 2315 UTC. Storm top features apparent that are associated with strong-severe weather at the surface include overshooting tops, enhanced-V’s, and above-anvil cirrus plumes. Gravity waves emanating from the updrafts, indicators of turbulence and caused by strong updrafts, are also more obvious in the GOES-16 data.
The Geostationary Lightning Mapper (GLM) is the other new earth-pointing instrument aboard the GOES-R series of satellites, and can detect total lightning activity with uniform detection efficiency. Data from the GLM are not yet available, however ground-based networks can be used to get a feel for how GLM data will generally look in AWIPS. Plotted is GOES-16 2-min visible imagery with Earth Networks 1-min Total Lightning Pulse density data, binned in 8-km grid boxes to match the resolution of the GLM, overlaid as semi-transparent. Pulses are a very basic variable, and when binned into grid boxes over a time period, provide a good measure of fluctuations in lightning activity. Max’s in total lightning density activity signify the core updraft regions of thunderstorms, which are also represented in visible imagery by a high degree of texture and overshooting tops. Rapid increases in lightning density signify rapid upticks in updraft strength, and thunderstorm intensification. Similarly, decreasing trends in total lightning activity will signify a weakening storm.
By early evening, the strong/severe storms had organized into a linear system, and while the severe threat had lessened, a flash flood threat had begun. A separate post will be written with details about the flood event.
– Bill Line, NWS
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
On the afternoon of 03/31/17, severe thunderstorms, including a couple long-lived supercells, moved across the southeastern most part of Virginia leaving behind a path of hail, wind damage, and at least one tornado, with two more reported in northeast North Carolina. These storms developed in association with a mid-level trough and related surface cyclone and cold front.
GOES-16 10.3 um “Clean” infrared animation valid on 03/31/17. Made using GEMPAK. *Preliminary, Non-Operaitonal Data*Click here to open in a new window.
The 10.3 µm “Clean” infrared channel on GOES-16 shows the large storm system transitioning to the East Coast with a dry slot that moves into eastern NC/VA quickly erupting into thunderstorms. Note how the cloud tops associated with the secondary band that develops in the afternoon quickly cool, then appear to jump to the Gulf Stream. This becomes a forecast challenge for the local National Weather Service offices as the storms transition from the land, to nearshore water, then to OPC’s offshore zones.
GOES-16 6.9 um mid-level water vapor animation valid on 03/31/17. Made using GEMPAK. *Preliminary, Non-Operational Data*Click here to open in a new window.
GOES-16 7.3 um low-level water vapor animation valid on 03/31/17. Made using GEMPAK. *Preliminary, Non-Operational Data*Click here to open in a new window.
The 6.9 µm and 7.3 µm water vapor channels show the enhanced warming (drying) in the mid to low levels where the atmosphere becomes unstable in the presence of near-surface warming/moistening and strong forcing with the upper-low coming in from the west. The supercell ahead of the main forcing remains isolated until later in its lifecycle with the dry slot aiding in the instability.
Zooming in on the area of thunderstorm development in the 7.3 µm low-level water vapor channel (~700 mb), the region of enhanced mid/low-level drying/warming ahead of the cold front within which isolated thunderstorms developed is apparent. Behind the cold front, that region of the atmosphere is expectedly cooler. The 7.3 µm channel is new with the GOES-R series, and when combined with the higher spatial and temporal resolution, allows forecasters to track (for the first time) low/mid-level features such as elevated mixed layers and cold fronts aloft.
00Z Weighting functions (UW/CIMSS) from the GOES Sounder 7.4 µm channel (very similar to ABI 7.3 µm) at MHX (just south of strongest t-storms) confirms that the drying/warming we are seeing is centered around 700 mb.
Radiosonde profiles at Morehead City, NC (left, ahead of cold front) and Roanoke, VA (right, behind cold front). Click here to open in a new window.
Looking at 00z soundings for comparison, mid-level drying was indeed present above near surface warming/moistening ahead of the cold front in Morhead City, NC leading to an unstable atmosphere. Meanwhile behind the cold front at Roanoke, VA, the cooler surface and moistening aloft led to a significantly less unstable environment.
GOES-16 10.3 um “Clean” infrared with the GLD-360 15 minute Lightning Density product overlaid, valid 0000 UTC 03/31/17 – 0645 UTC 04/01/17. Made using GEMPAK. *Preliminary, Non-Operational Data*Click here to open in a new window.
The 10.3 µm “Clean window” infrared channel overlaid with the 15-minute GLD-360 lightning density product produced at OPC, shows the rapid increase in lightning activity as the storms in the dry slot mature. This lightning density has proven quite useful to forecasters as a proxy to the Geostationary Lightning Mapper (GLM) that is located on GOES-16. The OPC forecasters can then use this information to characterize the thunderstorms as they move offshore into active shipping and fishing areas.
These storms developed within mesoscale domain sector (MDS) 1. This meant that 1-min imagery was available for this event even though no domain was requested, and because a domain was not requested elsewhere. The 1-minute, 0.5 km 0.64 µm “Red” visible imagery shows isolated supercell thunderstorms developing out ahead of the cold front in a warm, moist atmosphere. Additional development is noted along the cold front, which raced towards and caught up to the isolated thunderstorms by sun down.
GOES-16 0.64 um “Red” visible, 1-minute imagery with the GLD-360 2-minute Lightning Density overlaid, valid from 2000 UTC to 2358 UTC on 03/31/17. Made using GEMPAK. *Preliminary, Non-Operational Data*Click here to open in a new window.
The 1-minute 0.64 µm “Red” visible imagery with the 2-minute GLD-360 lightning density overlaid shows the uptick in lightning associated with the isolated supercell that moves through Chesapeake, VA and exits around Virginia Beach. Note the increased lightning intensity around the time of the tornado.
Forecasters are looking forward to using the GLM data with the imagery to help better forecast thunderstorm over land and especially over the oceans.
The preliminary storm surveys from the Wakefield, VA NWS Weather Forecast Office are included below for your convenience.
Thanks for reading!
Michael Folmer (CICS) and Bill Line (NWS)
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
The GOES-16 7.3 and 10.4 micrometer bands show the evolution of two extreme rainfall events in northern Peru and southern Ecuador during the evenings of March 21 and March 23, 2017. Rainfall in this region of the world comes in the form of downpours from evening thunderstorms. The warming of sea surface temperatures to readings over 29°C largely enhances these storms. When these temperatures are present, and under favorable synoptic setups, storms grow into large storm clusters that are capable of producing 4-8 in of rain in a few hours. The heaviest rains often develop in areas where the southern band of the Intertropical Convergence Zone (ITCZ) enters the coast.
Summary of the processes that seem to have played a role on the development of the 2017 Coastal El Nino event. Click here to open in a new window.
The thunderstorms exhibit a marked diurnal cycle. Convection develops during the late afternoon in the western slopes of the Andes and interior of the coast. While propagating westward into the evening, ongoing convective cells interact with diurnal breezes and unstable air masses that brew over the coast during the morning and afternoon. The additional moisture convergence and instability boosts the thunderstorms leading to heavy evening rains. The storms tend to rain the heaviest during the evening and near midnight, to then migrate west into the Pacific Ocean while losing organization. The storms of the evening of March 21st produced over 12 hours of rainfall in some locations. Several stations reported totals over 4 inches, and major flooding occurred in the cities of Piura, Paita and Talara, among others.
GOES-16 data will be of great use to improve the weather forecasts in Peru. The improved spatial and temporal resolution, plus the additional spectral bands, provide much more information that will serve to better understand and monitor the complex processes involved in these heavy rainfall events. Better monitoring implies better forecasts. GOES-16 data will allow forecasters to fine-tune the location of the potentially heaviest rains, better estimate storm propagation, and estimate regions of intensification and weakening.
GOES-16 7.3 um low-level water vapor animation showing the deep convection over northwest Peru and adjacent areas valid from 03/21/17 – 03/24/17. *Preliminary, Non-Operational Data* Click here to open in a new window.
As an example, data from the 7.3 μm channel can be used to monitor the locations where the largest low-mid tropospheric water vapor content is present. This helps to narrow down the location of the ITCZ, and provides information about the amount of moisture that may be available for rain. By contrasting the structure and movement of cirrus versus low-mid tropospheric background water vapor, the 7.3 μm channel provides information about atmospheric motion at different levels, and potential areas of enhanced upper divergence.
GOES-16 10.3 um “clean” infrared animation showing the same thunderstorms clusters as in the previous animation. *Preliminary, Non-Operational Data* Click here to open in a new window.
The 10.3 μm band provides more insight about what is occurring in the lower troposphere. This band is particularly useful to find surface features such as mesoscale convergence bands that form within the ITCZ, which produce a localized enhancement of rains; and to evaluate low-level winds. In this region of the world, weak surface winds or westerlies are favorable for strong evening convection, as they enhance diurnal onshore breezes. The 10.3 μm channel also provides more detail about the evolution of shallow convection. It provides insight about regions where convection might develop, and also suggests where low-level inversions may be present, from horizontally expanding warm clouds and waves propagating in these environments.
Thanks for reading!
Jose Galvez (WPC), Michael Folmer (CICS), and Michel Davison (WPC)
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
On 03/17/17, Mr. Clayton Johnson of Jamaica’s meteorological service and alumnus of the WPC International Desks, contacted Mike Davison for a threat assessment. The forecasters at both offices noted a band of training showers and thunderstorms stretching from Jamaica to the southwest portion of Haiti.
“The GOES-16 higher temporal and spatial resolution allowed our forecasters in the Tropical Desks to issue a higher confidence forecast while supplementing data from our operational weather models and lower resolution GOES-13 imagery”. The current position of GOES-16 at 89.5 W offers an ideal location to monitor convection in the northern portion of the Caribbean using the CONUS domain. With imagery available every 5 minutes, it is now possible for forecasters in this region to look at satellite updates as forecasters in the U.S. look at radar.
This information was quickly relayed to Clayton Johnson in Jamaica, and he was able to issue timely flash floods warnings for the NE Parishes of Portland and Saint Mary.
GOES-16 0.64 um visible animation shows showers and some storms between the southwest tip of Haiti and northeast Jamaica on 03/17/17. (Preliminary, Non-Operational data )
Note: The black spots are reflectance values that have been exceeded during the midday hours and is a known problem. Engineers are working on a fix.
GOES-16 10.3 um “clean window” infrared animation of the same event on 03/17/17. (Preliminary, Non-Operational data)
Thank you for reading!
Michael Folmer & Mike Davison
“The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. Users bear all responsibility for inspecting the data prior to use and for the manner in which the data are utilized.”
From our colleagues at NASA SPoRT, here are a couple animations of the first GOES-16 imagery (Air Mass RGB and Band 2 or 0.64 um imagery at 500 m resolution!!!). Enjoy!
Much of the GOES-14 super rapid scan operations for GOES-R (SRSOR) has been spectacular, but maybe I’m biased. . .this morning’s sunrise of Hurricane Marie was spectacular! I overlaid the GLD-360 lightning feed on top of the 1-minute imagery (1 to 1) and noticed some interesting observations. For one, it was evident that the eye was slowly clouding over which was unfortunate. Also. . .all of the lightning activity (what little existed) was well to the northeast, closer to land. My question here. . .does this mean there was no lightning in Marie, such as intracloud? This is where the Geostationary Lightning Mapper (GLM) will be a very useful tool in the future. It is important to note that Marie was in a rather steady-state this morning, with a possible eyewall replacement cycle on the way. . .so this may account for no lightning strikes in the eyewall.
GOES-14 SRSOR with Vaisala GLD-360 lightning strikes overlaid. Special thanks to James Kells (OPC) for helping with this animation. (Click on animation to expand in another window)
