Faka-Union Fire (Southwest Florida)

The Faka-Union Fire, located in southwest Florida has burned over 9,000 acres with only 50% containment. The fire is located near the Picayune Strand State Forest. The fire started out as a ‘prescribed burn’ last weekend, but due to erratic weather conditions, started to burn out of control. The smoke and fires have caused temporary road closures in southwestern Florida, however, as of 9 March 2018, no structures have been burned. For additional information on the Faka-Union Fire, click the following link.

The latest CIRA – GeoColor loop of the fire via the CIRA-RAMMB Slider between 15-18 UTC, 9 March 2018 (shown below). Notice the elongated trail of grey/white smoke, emanating from the fire.


Below, is the latest Near-Constant Contrast (NCC) satellite imagery of the Faka-Union fire from this past week, 2-8 March 2018. NCC imagery is also known as ‘nighttime visible’ imagery, that can identify atmospheric features, and sense emitted and reflected light sources during the nighttime. All times are between 6-8 UTC. Notice the change in emitted lights from the fire (embedded in the yellow circle). The fire is close in proximity to the emitted city lights of Naples, Florida.


To get an idea of where the smoke from the fire will disperse, one can utilize the ‘experimental’ High Resolution Rapid Refresh (HRRR) Smoke Model. The model had been developed to simulate emissions and the transport of smoke from wildfires. The model is at 3 kilometer spatial resolution and is initialized everyday, at 00, 06, 12, and 18 UTC, and the model produces 36-hour forecasts.

For the Faka-Union Fire, click on the following HRRR Smoke link, to see where the smoke from the fire is forecasted to disperse. The model animation was initialized at 12 UTC, 9 March 2018.

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Synthetic imagery from the NSSL WRF-ARW for 7 March 2018 event

A nor’easter occurred on 7 March 2018 which resulted in heavy snow, strong winds and rain across portions of the Northeast U.S.  In this blog entry we’ll examine the performance of the NSSL WRF-ARW via synthetic water vapor imagery in relation to the cyclogenesis aspects.

The following 4 panel display:


shows the following:

Upper left:  GOES-16 7.34 micron imagery (5 minutes)

Lower left: NSSL WRF-ARW synthetic 7.34 micron imagery from the 00Z 7 March run (hourly)

Upper right:  GOES-16 6.95 micron imagery (5 minutes)

Lower right: NSSL WRF-ARW synthetic 6.95 micron imagery from the 00Z 7 March run (hourly)

Early in the loop we observe colder cloud tops offshore, adjacent to a dry slot just west of that region, followed by colder cloud tops  associated with proximity to the upper low.  Soon thereafter, we see the rapid development of clouds in proximity to the upper low (the red oval on the image below):

The warm conveyor belt is denoted by the red “WCB” at this time.  Up to this point, this may be considered a cold air type of cyclogenesis event.  However what happens afterwards in the yellow oval above would transition this to an (more intense) instant occlusions type of cyclogenesis.  In the yellow oval, watch the development of convection.  This signifies the development of a secondary warm conveyor belt which peels cyclonically from the warm conveyor belt back towards the position of the upper low.  Once occlusion begins, this is generally referred to as the TROWAL airstream.  The significance of this is that the TROWAL advects air from the warm sector, back towards the low, allowing more baroclinic energy for the cyclone to act upon.  This generally results in rapid pressure falls, and associated hazardous weather (heavy precipitation, strong winds etc.).  A conceptual diagram with these features can be viewed on slide 3 of this training module: http://rammb.cira.colostate.edu/training/visit/training_sessions/goes_r_cyclogenesis_life_cycle/video/

The NSSL WRF-ARW output, as viewed via the synthetic imagery generally did a good job capturing the development of the various components of cyclogenesis discussed above, albeit the position was slightly off.  The synthetic imagery provides an efficient visual comparison between model output and observations (GOES), allowing for a rapid assessment of how the model is performing.  This assessment in model forecast confidence allows the forecaster to have more or less confidence in future forecast hours.  The region of rapidly cooling cloud tops denoted by the red oval shows a more uniform extent of colder cloud tops compared to the NSSL WRF-ARW synthetic imagery.  This is primarily due to a known weakness in the WSM6 microphysics scheme used in the NSSL WRF-ARW.  Due to this known weakness, it’s the location and timing of the colder cloud tops that matters, not so much the areal extent of colder cloud tops.

The GOES-16 1-minute visible imagery provided a spectacular view of the development of the convection associated with the TROWAL:


An alternate view of the same scene is the Day Cloud Phase Distinction RGB, which provides different colors to various growth stages of the convection:



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Tropical Cyclone Dumazile

A tropical cyclone has been present in the Indian Ocean, the past few days. Yesterday, on 4 March 2018, tropical cyclone Dumazile skirted along the coasts of Madagascar and La Reunion bringing high winds, heavy rain and storm surge along the way. To persons that are not familiar, Madagascar is located on the southeast side of Africa, a remote island, embedded in the western Indian Ocean.

A Day/Night Band (DNB) image below shows the location of Dumazile, just east of Madagascar at 2137Z , 4 March 2018 (0037Z, 5 March 2018, local time). The nighttime satellite image, highlights the tight-circulation, the cloud convected tops and the large areal extent of Dumazile. Convected cloud tops are indicative of heavy precipitation.  As of early this morning, 5 March 2018, Dumazile had maximum sustained winds of 120+ miles per hour (mph) and is forecasted to move south, southeast (i.e. away from Madagascar) at approximately 13 mph, according to the Joint Typhoon Warning Center (JTWC).

For more information on Dumazile, click on the following web-link.

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East Coast Weather….

Winter Storm Riley inundated the northeast United States with strong winds, storm surge and high amounts of rain and snow. Current snowfall totals over the northeast can be seen via the National Weather Service – Snowfall Reports web-link.  The screenshot below, shows the snowfall distribution over the northeastern United States, with current snowfall observations (as of 2230 UTC, 2 March 2018) ranging from just a few inches (blue colors) to over 20 (red, maroon colors) in some areas!

A Near-Constant Contrast (NCC) image (below) taken at 0645 UTC, 2 March 2018, shows the large, areal extent of Riley, as Riley produced damaging winds and power outages across the northeast. Corresponding cloud cover (reflected light sources) and city lights (emitted light sources) can be also be seen in the imagery.

Another feature to highlight in the NCC imagery is the cold front across the state of Florida. Using the same image from above and zooming in to the state of Florida, notice the ambient cloud cover and elongated line of clouds, expressed horizontally.  Although this is a static image at 0645 UTC, 2 March 2018, one can verify the elongated line of clouds is a cold front passing through the state, via surface observations.

Using surface observations at a similar time stamp (0658 UTC, 2 March 2018), there is a dramatic shift in winds, from north-northwesterly in northern Florida, to west-southwesterly winds in southern Florida (see red circle). The rapid change in wind direction is an indication of a front moving through the area, in this case, a cold front.

To see the cold front advect south, through the state of Florida, see the following animation. Notice the change in air temperatures (values in red), from low-to-mid 70’s to the upper 50’s, and lower 60’s. Animation is from 0058-1458 UTC, 2 March 2018. (Images courtesy of RAP Real Time Weather data)

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