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Presentation of Interim Results at Annual Meeting of American Meteorological Society

Interim results were presented at the AMS meeting in Atlanta, Georgia by Earth Networks with Dr. BAH in attendance:

Session 8B (35017): International Applications Session: Latest Challenges for Disseminating and Accessing Weather Data, Forecasts and Warnings; Creating an Operational End to End Early Warning System Infrastructure in Guinea (West Africa) is scheduled as Paper 8B.6 of the session from 17:15 until 17:30 on Wednesday, 5 February 2014, Room C105.

Content of the presentation included:
– verification of observation network up-time and data reliability
– comparison of lightning strikes detected by the network to satellite data
– storm detection cases with emphasis on early warning and rainfall estimates
– forecast performance verification in comparison to top global models
– ways the information is being disseminated and future plans

Presentation slides can be viewed at these links –

EN_CCA_Program_AMS_020514

https://dl.dropboxusercontent.com/u/74029884/EN_CCA_Program_AMS_020514.pdf

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Dr. BAH shares his insights with the top management of NOAA and Earth Networks at AMS Meeting.

Dry Season Underway, Storms Still Detected Offshore

3 December 2013, 13:00 UTC: Guinean meteorologists have been closely monitoring the shift in seasons over the last month as the convergence area that produced the daily rains from June through October has steadily shifted south toward the equator.

Rainfall recorded around the country at the live weather station locations has shown a steady drop in measureable rain since Oct. 31. For example, the weather station in Fria has recorded just 3.3 cm of rain in the last 33 days. In October, the location recorded nearly 10 times as much rain – measuring 29.2 cm in 31 days.

The Guinea ENcast forecast system shows that the dry season will be well entrenched, with virtually no chances for rain over the next 6 day. Temperatures remain warm with high temperatures reaching 31-33 C nearly every day.

Forecasts show the dry season is well underway with warm temperatures and virtually no chances for rain.

Forecasts show the dry season is well underway with warm temperatures and virtually no chances for rain.

The Guinea Total Lightning Network has been able to track the movement of the convergence area producing storms well away from the country and out over the shipping lanes leading into the port of Conakry.

Lightning over a period of 30 minutes is shown in an intense storm detected by the Guinea Total Lightning Detection Network.

Lightning over a period of 30 minutes is shown in an intense storm detected by the Guinea Total Lightning Detection Network.

Today, a very intense storm developed southwest of the city and the network captured the significant lightning that was indicating a strong storm with high winds and intense rainfall.

Guinea PulseRad tracked very intense thunderstorms thate developed near the coast and tracked offshore.

Guinea PulseRad tracked very intense thunderstorms thate developed near the coast and tracked offshore.

Lightning rates reached thresholds that caused the automated system to issue Dangerous Thunderstorm Alerts for these areas over the open oceans.

An intense storm detected by the Guinea Total Lightning Detection Network with associated Dangerous Thunderstorm Alerts issued due to the intensity detected.

An intense storm detected by the Guinea Total Lightning Detection Network with associated Dangerous Thunderstorm Alerts issued due to the intensity detected.

Sea Breeze Storms Rumble in SW Guinea

12 November 2013: Late this afternoon and early evening, strong storms have been slowly tracking along a sea breeze front just inland of Conakry and along highways N4 and N3. The strongest of the storms was just north of N4 between Forecariah and Conakry this afternoon and tracked northwestward decaying and regenerating into an even stronger storm north of Conakry.

PulseRad simulated Radar shows a very strong thunderstorm north of Conakry.

PulseRad simulated Radar shows a very strong thunderstorm north of Conakry.

The Guinea Total Lightning Detection System triggered several Dangerous Thunderstorm Alerts (DTAs) to be issued along these highways as this storm drifted norhtwest.

Dangerous Thunderstorm Alerts are shown as strong storms with very frequent lightning rumbled north of Conakry around 4:30 p.m. today.

Dangerous Thunderstorm Alerts are shown as strong storms with very frequent lightning rumbled north of Conakry around 4:30 p.m. today.

Despite all the activity just 20 km inland, Conakry remained dry for the most part as stable winds off the Atlantic kept the storms just inland. An outflow wind gust from the storm did peak at 73 km/hr as the storm skirted to the northeast.

Rainfall estimates by the Guinea PulseRad system were showing rainfall totals of 15-50 mm had fallen in just over an hour in these areas.

PulseRad precipitation estimates show rainfall largely avoided Conakry although 15-50 mm of rain fell in just 60-90 minutes just 25 km away.

PulseRad precipitation estimates show rainfall largely avoided Conakry although 15-50 mm of rain fell in just 60-90 minutes just 25 km away.

Another strong storm just west of Mamou also had very heavy rainfall occur along N1 just 20 km to the west.

Rapidly Developing, Strong Storms Tracked Over Night in Conakry

11 November 2013: A very strong thunderstorm developed rapidly just SE of Conakry as the Guinea Total Lightning Detection System caught the rapidly developing, slow moving storm and issued a Dangerous Thunderstorm Alert (DTA) at about 12:30 a.m. The DTA is issued for the intense storm due to the high rate of intracloud (IC) and cloud-to-ground (CG)lightning indicating the storm was capable of high wind gusts, and extremely heavy rain.

The video shows multiple DTAs issued for the city as the storm slowly moved toward the city. After 1 a.m., the storm regenerated and new DTAs were issued for the NE portion of the city as well.

Slow motion:

The slow moving storms allowed for very heavy rain to fall in less than one hour.

PulseRad Rainfall Estimates

The slow moving storm dumped rainfall of 30-60 mm over the city of Conakry

Strong Storm Hits Boke

5 November 2013, 19:00 UTC: A strong thunderstorm that formed to the east of Boke was tracked by meteorologists as it strengthened into a dangerous storm just east of Boke at about 6:45 p.m. this evening.

Guinea1PR

The storm was detected to have lightning rates exceeding 40 flashes per minute by the Guinea Total Lightning Network.

Guinea4RT

The Total Lightning Detection System issued an automated Dangerous Thunderstorm Alert (DTA – Purple Polygon) for this storm for the likelihood of intense rain, frequent lightning and gusty winds. The DTA gave Boke about 20 minutes lead time before these affects hit.

Wind Gusts Exceeded 70 km/hr

Wind Gusts Exceeded 70 km/hr

Winds gusted to 71 km/hr as the storm approached with lightning flashing just to the east. When the storm rolled into the city, real-time observing instruments recorded a more that 5 degree C temperature drop in a matter of minutes.

Temperatures Dropped 5 Degrees in Minutes

Temperatures Dropped 5 Degrees in Minutes

Rain rates were intense, producing flash flooding as rain fell at a rate of more than 100 mm/hr. Over 40 mm of rain fell in less than 30 minutes.

Rain Rates Topped 100 mm/hr

Rain Rates Topped 100 mm/hr

Rainfall from the storm was also estimated to be between 35 and 50 mm - mostly falling in about 30 minutes.

Rainfall from the storm was also estimated to be between 35 and 50 mm – mostly falling in about 30 minutes.

 

Afternoon Sea Breeze Storms Tracked in Sierra Leone and Liberia

4 November 2013, 20:00 UTC: Afternoon and evening storms were being tracked by Guinea meteorologists as they began forming along a sea breeze convergence zone in Sierra Leone and Liberia. Total lightning detection allowed forecasts to see a fairly extensive line of storms about 20 miles inland from the coast. PulseRad simulated radar showed these storms very well.

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The Guinea Total Lightning Detection Network was showing wide spread lightning occuring with several storms producing frequent lightning at a rate to cause the automated alerting system to produce Dangerous Thunderstorm Alerts (DTAs).

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The image below shows the most intense of these storms along the Sierra Leone and Liberia border.

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The Guinea TLDN detected lightning frequency over 20 flashes per minute and issued a DTA for the storm. This storm was producing heavy rain, gusty winds and very heavy downpours.

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Afternoon Strong Storms Again, But Fewer

Update – 15:30 UTC: Guiinea meteorologists continue to monitor a strong storm between Conakry and Kindia near the N1 highway. PulseRad radar estimates indicated that 75-100 mm of rain has fallen in the last 60-90 minutes. Recently, winds have gusted to 90 km/hr in Conakry. Flash flooding is occuring in this region. Dangerous Thunderstorm Alerts continue to be in effect for this storm.

PulseRad precipitation estimates indicate 75-100 mm of rain has fallen since 2 p.m.

PulseRad precipitation estimates indicate 75-100 mm of rain has fallen since 2 p.m.

31 October 2013, 14:30 UTC: Guinea meteorologists are once again tracking the development of afternoon thunderstorms across Basse Guinea, the western region of the country. Today, storm development has been less due to drier air in the mid-levels across the northern and northwestern part of the country. More significant moisture is evident in the southwest and this is where scattered storms have begun to develop. Strong storms have formed in the hills to the northeast of Conakry and near Kindia and Mamou.

Very intense storms have developed betwen Conakry and Mamou.

Very intense storms have developed betwen Conakry and Mamou.

The Guinea Total Lightning Detection System has tracked the development of two very strong storms along the N1 highway running between Conakry and Mamou. The system has generated Dangerous Thunderstorm Alerts for these storms for dangerous lightning, very heavy rain and gusty winds.

Very frequent lightning has triggered the issuance of Dangerous Thunderstorm Alerts (purple polygons) in this region.

Very frequent lightning has triggered the issuance of Dangerous Thunderstorm Alerts (purple polygons) in this region.

PulseRad, simulated radar generated from precipitation rate estimates base on the total lightning detection was showing some extreme rainfall rates. The storms were moving very slow and rainfall totals in the last 30-60 minutes have been locally heavy from 25 – 40 mm/hr.

Rainfall in just an hour has exceeded 50 mm in a few locations due to the slow movement of the storms.

Rainfall in just an hour has exceeded 50 mm in a few locations due to the slow movement of the storms.

Just after 2:30 p.m. local time in Conakry a strong outflow wind gust was observed in the city – gusting to 73 km/hr.

Live observations in Conakry show that the storm to the northeast caused a wind gust across the city that reached 72 km/hr.

Live observations in Conakry show that the storm to the northeast caused a wind gust across the city that reached 73 km/hr.

Hourly updating forecasts using the live station data indicate that precipitation probabilities will be high through the afternoon due to the slow moving nature of the storms.

Due to the slow movement and copious moisture in the region, forecasts indicate high probability for storms until after sunset.

Due to the slow movement and copious moisture in the region, forecasts indicate high probability for storms until after sunset.

Afternoon Storms Again Hit NW Guinea

30 October 2013, 17:00 UTC: Meteorologists at the Guinea Meteorological Directorate have been monitoring another round of afternoon storms developing over the hills and highlands of Basse Guinea. As has been an almost daily occurance that a watch can be set by, storms have formed over the higher terrain where continental easterlies converage with Atlantic sea breezes.

Converging winds (blue line) along with day time heating over higher elevations have created daily instability to cause thunderstorm development.

Converging winds (blue line) along with day time heating over higher elevations have created daily instability to cause thunderstorm development.

These locations have seen a daily parade of storms that meteorologists have monitored each day for potential severity. Each day, a number of storms have developed into potentially severe storms based on total lightning data detected by the Earth Networks Total Lightning Network. Dangerous thunderstorm alerts have been issued for the storms that show a slow drift toward the west and the coast.

Simulated radar based on the total lightning detection shows strong storms in NW Guinea. An almost daily afternoon occurance lately.

Simulated radar based on the total lightning detection shows strong storms in NW Guinea. An almost daily afternoon occurance lately.

Meteorologists tracking the storms expect them to begin to develop around noon-time and slowly move westward. The storms have been noted to have life spans of a couple hours as storms die and reform. Typical storms can drop 25-50 mm of rainfall in an hour.

Total rainfall over the past 7 days in this region can also be estimated by the meteorologist using the PulseRad simulated radar. Radar reflectivity is translated into estimated rainfall at the surface. Meteorologists have been able to use this system to show that parts of Fouta Djallon have had 150 – 200 mm of rain in the past 7 days and are very prone to flash flooding as new storms approach.

Simulated radar based on the total lightning detection shows strong storms in NW Guinea. An almost daily afternoon occurance lately. Rainfall totals the past seven days have exceeded 8" in part of Fouta Djallon.

Simulated radar based on the total lightning detection shows strong storms in NW Guinea. An almost daily afternoon occurance lately. Rainfall totals the past seven days have exceeded 200 mm in part of Fouta Djallon.

Strong Storms Rumble Across Basse Guinea Toward Coast

29 October 2013, 17:00 UTC: Typical afternoon storm development has become severe across the northwest portion of Basse Guinea as storms developing across the hills and highlands have interacted with a steady sea breeze that has pushed inland from the Atlantic.

Simulated Radar shows very strong storms developing.

Simulated Radar shows very strong storms developing.

Guinea meteorologists have been monitoring the simulated radar system, PulseRad to determine the locations of the most severe storms. Very strong storms in the prefectures of Fria, Boffa and Dubreka have been determined to be severe based on measurements taken by the Guinea Total Lightning Detection Network.

PulseRad, simulated radar based on total lightning detection show strongest storms in Dubreka and Boffa

PulseRad, simulated radar based on total lightning detection show strongest storms in Fria, Dubreka and Boffa

The automated network generated Dangerous Thunderstorm Alerts (DTA) for several strong storms in the area. The lightning rates detected in these storms were determined to reach a frequency to cause the meteorologists to be concerned they would be producing flooding rainfall rates, gusty winds and very frequent lightning.

The strongest of the storms had automated Dangerous Thunderstorm Alerts issued based on thresholds exceeded determined by the Total Lightning Detection Network.

The strongest of the storms had automated Dangerous Thunderstorm Alerts issued based on thresholds exceeded determined by the Total Lightning Detection Network.

The strongest storm was tracking north-northwest into Boffa and south of the city of Fria. This storm was likely producing flash flooding and gusty winds over 50 km/hr.

Image shows the strongest of the storms and the associated Dangerous Thunderstorm Alert that was automatically issued.

Image shows the strongest of the storms and the associated Dangerous Thunderstorm Alert that was automatically issued.

The storm had shown a steady increase in lightning frequency over the past hour. Lightning rates had approached 60 flashes/min. Meteorologist monitoring the storms have noticed a pulsing nature of the storm cells with storms weakening and dissippating over a time period of 2-3 hours. New storms continue to be expected to develop, track northwestward and decay till about 1 hour after sunset, after which all activity should decrease rapidly.

The Guinea Meteorology Directorate's Total Lightning Detection System shows that lightning rates can be tracked in individual storms to determine the severity.

The Guinea Meteorology Directorate’s Total Lightning Detection System shows that lightning rates can be tracked in individual storms to determine the severity.

Evening Storms Hit Fria Again

22 October 2013, 20:45 UTC: Storms that have developed over Moyenne Guinea and Basse Guinea have tracked westward all afternoon and evening, and once again as in the last few days, a storm storm is entering Fria and Dubreka Prefectures. The city of Fria was put under a Dangerous Thunderstorm Alert by the Guinea Meteorological Department around 8:20 p.m. for a strong storm approching from the east.

The Guinea Total Lightning Network detected massive amounts of intracloud and cloud-to-ground lightning in the storm and the PulseRad system showed the strong storm via simulated radar.

PulseRad, or simulated radar shows the strong storm hitting Fria.

PulseRad, or simulated radar shows the strong storm hitting Fria.

The storm was producing rain rates in excess of 50 mm/hr and causing flash flooding in the city as predicted by the Dangerous Thunderstorm Alert.

Guinea1RT

The storm also produced a wind gust at the live automated observing station in Fria recorded at 77 km/hr. The storm is forecast to continue over the area for the next 45 minutes and could produce up to 2″ of rainfall during that time.

Guinea2RT