| TRAINEE INFO + PDF |
TITLE |
ABSTRACT |
30. Julio Cabanerit
Country: Venezuela
Desk: Tropical
Training: Forecaster
Date: 2016 July
PDF in English
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Interaction between a shear line and the Inter Tropical Convergence Zone
in the Northwestern Coast of Venezuela. 25 November 2010 Heavy Rainfall Event.
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A heavy rainfall event occurred in the northern coast of Venezuela during the last week
of November 2010. The heavy rains resulted from the interaction of the intertropical convergence
zone, well to the north of its climatological position, and a shear line associated with a
strong upper trough in the northern Caribbean. Some predictors explored
and described include low-level moisture convergence, a few stability indices,
SSTs and potential vorticity as an indicator of a strong upper trough over the northern Caribbean.
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29. Lorne Salmon
Country: Antigua
Desk: Tropical
Training: Forecaster
Date: 2015 September
PDF in English
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Determining the potential for tornadoes in Northeast Caribbean Cyclones:
Tornado in Antigua during Tropical Storm Chantal on 8 July 2013.
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A tornado went through the island of Antigua during the passage of
Tropical Storm Chantal about 280km to its west-southwest. This
study explores the behavior of different predictors identified
by Oderlinde (2002) using GFS model data. It was found that 0-3km
shear values exceeding 15m/s were present during the event. Comparison
of the TFFR sounding against model data suggests that the model was
underestimating the amount of shear. The tornado also occurred in
the quadrant/sector of the storm, at a distance
from the center and at a period of the diurnal cycle described to
be favorable for tornadoes.
the
an important predictor is the low-level
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28. David Romero
Country: Chile
Desk: South American
Training: Forecaster
Date: 2015 September
PDF in English
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Heavy Rainfall Events in Southern Chile during El Niño 2015
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Five heavy rainfall events that affected Southern Chile during
El Niño winter of 2015 are studied. The goal is to determine
predictors and thresholds to better recognize the need to issue an
advisory (alerta) before future similar events. The study found many
similarities between the several cases studied. The most remarkable
features were robust subtropical moisture connections/atmospheric
rivers that arrived with precipitable water values of 20-35mm, very
high for Southern Chile. Upper jet dynamics and orographic interactions
also played a role. The direction of the low-level winds seem to matter
for heavy rains extending from western slopes into the Central Valley.
The latter occurred during the case where the low-level winds were
west-northwesterly instead of north-northwesterly.
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27. Dwight Samuel
Country: Suriname
Desk: Tropical
Training: Forecaster
Date: 2015 July
PDF in English
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TUTT-Induced Hail Event in Suriname
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The conditions that lead to the unusual January 2014 hail event in Suriname
are studied. The results show that the thermodynamic parameters used to
predict hail were marginally favorable. It appears that the dynamics were
unusually strong for the latitude. Hail occurred when a potent upper trough accompanied
by several short waves interacted with a perturbation arriving in the
easterly trades during the diurnal peak of instability. A few
predictors involved in the event are analyzed with ensemble forecasting
constructed with four GFS model simulations. The results suggest that the
model was able to resolve thermodynamic quantities more consistently than
dynamic ones.
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26. Gina Charpentier
Country: Chile
Desk: South American
Training: Forecaster
Date: 2015 July
PDF in English
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Forecasting Turbulence in the Austral FIR and Wind Gusts in SCCI:
15-16 June 2015 Case Study
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The study applies methods to evaluate the potential for turbulence to
a case study of enhanced turbulence that affected extreme Southern Chile.
The study also proposes a method to forecast near surface wind gusts
in Southern South America. These are not only associated with vertical wind shear
at low-levels but they seem to be enhanced by isentropic descent in the
rear tier of occluded lows. This study developed Wingridds macros/scripts that can
be used to forecasts wind gusts in Southern South America upon numerical model data.
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25. Eusebio Cisneros
Country: Peru
Desk: South American
Training: Visiting Instructor
Date: 2015 June
PDF in English/Spanish
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Mechanisms that favored the generation of thunderstorms in Iquitos,
Peru during February 2015.
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This study explores the mechanisms that lead to the development/arrival
of thunderstorms in the Iquitos, Peru airport during February 2015
affecting air travel. The study identifies several predictors and
thresholds, and describes the influence ov waves in the trades, the
Venezuela/Colombia northeasterly low-level jet, and a lee trough
that forms between southern Venezuela and northern Peru during
periods with northeasterly trades in northern South America.
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24. Franklin Unsihuay
Country: Peru
Desk: South American
Training: Visiting Instructor
Date: 2015 May
PDF in English
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Fog events in the city of Arequipa, Peru during February 10 2015.
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This study explores the conditions that lead to the periods of dense fog
at the city of Arequipa, Peru during February 10, 2015.
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23. Marcelo Schneider
Country: Brasil
Desk: South American
Training: Forecaster
Date: 2015 May
PDF in English
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Study of heavy rainfall events in the Sao Paulo Region
after the peak of the Severe Drought of 2014-15.
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This study explores the conditions that led to two heavy rainfall
events in the Sao Paulo area during February and March 2015, after
the severe drought of 2014-15. The study looks into interactions
between several scales: global, synoptic and mesoscale; and also
explores the role of teleconnections, ENSO, MJO and rossby wave
propagation.
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22. Simon Craig
Country: Trinidad and Tobago
Desk: Tropical
Training: Forecaster
Date: 2015 May
PDF in English
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Extreme Rainfall Event in Trinidad and Tobago. October 1-4 2014. |
Several rounds of heavy rain and strong winds affected Trinidad and Tobago during the
first four days of October 2014. This case study explores the factors that lead to
these conditions and the way it was analyzed and forecasted.
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21. Victoria Calle
Country: Peru
Desk: South American
Training: Visiting Instructor
Date: 2015 April
PDF in English
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Heavy rains and mudslides in the Central Andes of Peru during 23 March 2015. |
A 5-day stretch of heavy rains and mudslides affected the Central Andes of
Peru during late March 2015. These led to the deadly March 23rd 2015 mudslide
in Chosica that killed 8, dissappeared 6 and displaced 250 families. The case study
explores the conditions that lead to the heavy rains and deadly Chosica mudslide
and the Weather Service/Warning Communication System responses.
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20. Vladimir Arreaga
Country: Ecuador
Desk: South American
Training: Forecaster
Date: 2015 March
PDF in English
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Heavy Rainfall Event in Ecuador. March 16-19 2015. |
Heavy rains affected most of continental Ecuador during the 16-19 March 2015
period, initially peaking over the Pacific Basin and then peaking over the Andes
and Amazon regions. The case study describes this event, including the
identification of heavy rainfall predictors for
the three aforementioned regions: the Pacific coast, the Andes and
the Amazon rainforest.
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19. Radjkoemar Nanda
Country: Suriname
Desk: Tropical
Training: Forecaster
Date: 2015 March
PDF in English
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The occurrence of radiation
fog and mist at the SMJP
airport
in Suriname. |
Fog is one of the meteorological situations that affects operations at the
Zanderij airport SMJP in Suriname. This study explores the climatology
of fog over SMJP, identifies relevant predictors, and tests these into
three recent fog events.
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18. Ricardo Duran
Country: Peru
Desk: South American
Training: Forecaster
Date: 2015 January
PDF in English
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Anomalous snowfall in South and Central Peru during January 2015.
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The unusually snowy January of 2015 in the Andes of Peru prompted
an interest to understand the underlying causes. This study focuses
on finding predictors for summer snowfall in the Peruvian Andes. Four
predictors and relevant thresholds were identified: (1) temperature
< -2.8°C in the 500-550 hPa layer, (2) moisture flux convergence
greater than 6x10^8 m-2 s-2 in the same layer, (3) relative humidity
greater than 75% in the same layer, and (4) omegas lower than -2 bar/s
in the 400-450 layer. Wingridds macros/scripts were developed
and tested succesfully during new snowfall events.
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17. Maclean JnBaptiste
Country: St. Lucia
Desk: Tropical
Training: Forecaster
Date: 2015 January
PDF in English
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Severe flooding event in St. Lucia during 8 November 2014.
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Hours of heavy rain affected St. Lucia during November 8 2014, which
lead to widespread flooding. An unusually strong upper trough
had displaced the Intertropical Convergence Zone northward into the
Windward islands, where a weak easterly wave entered in phase
with a short wave upper trough. The predictors and thresholds identified were
(1) precipitable water > 50mm and (2) GDI > 40. Enhanced
upper divergence associated with the short wave upper trough
played a role. Continuous model corrections however
limited confidence on the establishment of threshold values
and event predictability.
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16. Mauricio Caroca
Country: Chile
Desk: South American
Training: Forecaster
Date: 2014 November
PDF in English
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Effects of a cold core low in Northern Chile during 13 September 2014.
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Strong cold core upper low off Northern Chile produced precipitation
in regions that usually receive very little rainfall. The system also
produced snowfall in the cordillera and dust storms in the Atacama desert.
The study explores the case applying different forecasting tools and methods
used at the South American Desk such as upper jet analysis, isentropic
analysis and the forecast funnel. It also discusses local applications of
GFS data such as the recognition of potential Atacama dust storms in
forecast wind profiles.
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15. Jose Medina
Country: Dominican Republic
Desk: Tropical
Training: Forecaster
Date: 2014 November
PDF in English
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Heavy rainfall event in the Dominican Republic during the wet-to-dry transition.
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Strong convection and heavy rains occurred on the afternoon of October 26 2015
as a cold front and shear line entered Hispaniola after several days under the influence of
a mid-level ridge. The study explores different aspects behind the evolution
of the event.
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14. Sergio Jalfin
Country: Argentina
Desk: South American
Training: Forecaster
Date: 2014 September
PDF in Spanish
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Severe thunderstorms and intense cyclogenesis in Central Argentina. August 22-26 2014.
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A sudden hailstorm affected Buenos Aires during August 24 2014, during the unraveling
of a strong cyclogenesis event. The study uses this case to go over a list of fields
that should be analyzed when forecasting severe weather in Argentina such as
mid-level height falls, advection of cyclonic vorticity at mid-levels, stability
indices, moisture availability and distribution in the vertical, upper jet dynamics.
etc. It also elaborates with further detail on the conditions that lead to the
development of hail storms in the Buenos Aires province.
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13. Pablo Valverde
Country: Costa Rica
Desk: Tropical
Training: Forecaster
Date: 2014 September
PDF in Spanish
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Mesoscale Convective Complex in the Caribbean Coast of Costa Rica. August 15-16 2014.
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A strong mesoscale convective complex developed off the Caribbean coast of Costa Rica
during the late night hours of August 15 2014 and meandered westward into coastal areas
producing rainfall totals of 50-160mm/day.
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12. Anete Fernandes
Country: Brasil
Desk: South American
Training: Forecaster
Date: 2014 July
PDF in Portuguese
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Trade wind disturbance in the Northeastern Coast of Brasil.
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A perturbation in the trades arrived in the Northeastern Coast of
Brasil producing rainfall totals near 300mm in three days in Natal.
The study explores the conditions that lead to the excessive amounts
and GFS model use and performance in the forecasting of such a
localized event.
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11. Juan Jose Amides Figueroa
Country: El Salvador
Desk: Tropical
Training: Forecaster
Date: 2014 July
PDF in Spanish
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Heavy rains in Northern Central America from Late Season
Cold Front and Pre-frontal Trough.
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A slow-progressing late-season cold front and pre-frontal
trough over Northern Central America lead to heavy rains over el Salvador.
Often these systems ffect the area in a time of the year when moisture
and instability are limited. But by early May airmasses over the region are
often less stable and moister. In this case, the pre-frontal trough and associated
weak winds stimulated the sea breeze, convective instability and aided
deep-layer moisture transport from the Tropical Pacific. This lead to recurrent
heavy thunderstorm development over El Salvador during May 01-03 2014.
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10. Tania Ita
Country: Peru
Desk: South American
Training: Forecaster
Date: 2014 May
PDF in Spanish
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Fog in the city of Lima, Peru on 21 April 2014.
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This presentation explores the synoptic conditions that lead to
a dense fog event at the Jorge Chavez International Airport near
Lima, Peru. The event responded to (1) onshore winds across a sharp
sea surface temperature gradient that transported a moist airmass
into a much cooler environment favoring saturation;
(2) confluence and convergence at 1000 hPa; and
(3) a strengthening of the sea breeze circulation,
which enhances subsidence and helps to strengthen the near-surface
temperature inversion that traps the fog near the ground.
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9. Pamela García
Country: Mexico
Desk: Tropical
Training: Forecaster
Date: 2014 May
PDF in Spanish
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Extraordinary hail storm in Xalapa, Veracruz, Mexico.
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A strong storm with tennis-ball-sized hail affected the city
of Xalapa, Mexico during 27 April 2014. The storms initiated
due to diurnal heating. Their severity was yet favored by
an increase in instability with respect to previous days as
well as a drying over 500 hPa. The latter increased evaporational
cooling and stimulated the formation of large hail.
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8. Silvia Santos
Country: Brasil
Desk: Tropical
Training: Forecaster
Date: 2014 March
PDF in English
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Activities in the Tropical Desk and Presentation of a Case Study.
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A summary of the Tropical Desk activities is here presented
together with a case study that elaborates on the interaction
of a tropical wave and a tropical upper tropospheric trough
(TUTT). A summary of the methods to determine the presence
of tropical, easterly and tutt-induced wave is also presented.
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7. Carmen Canul
Country: Mexico
Desk: Tropical
Training: Forecaster
Date: 2014 March
PDF in English
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Snowfall event over Sierra de Arteaga in Coahuila, Mexico.
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A heavy snowfall event occurred in the northeastern mountains
of Mexico during late December 2013. This study explores the
conditions behind the heavy snowfall event and expands on
the tools and fields for its forecasting.
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6. Valeria Vicente
Country: Argentina
Desk: South American
Training: Forecaster
Date: 2014 January
PDF in English
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Severe convection event in north-central Argentina and Uruguay.
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This study focuses on the South American Desk routine and
on its application to the forecasting of severe convection
in north-central Argentina.
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5. Peter Fearon
Country: Jamaica
Desk: Tropical
Training: Forecaster
Date: 2014 January
PDF in English
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Echo training event over the Northern Bahamas. November 19-20, 2013.
|
An echo training event occurred in the northern Bahamas
during November 2013. A cold front approached the region and
led to the establishment of deep-layer easterly flow in a
region prone to the generation of storm cells. These produced
large rainfall amounts in the northern Bahamas and especially
southeastern florida, as cells followed the same path. This
work expands on the echo training mechanism and on the
predictors for such event.
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4. Aldo Sánchez
Country: Argentina
Desk: South American
Training: Forecaster
Date: 2013 November
PDF in Spanish
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Severe thunderstorms in North-Central Argentina during
October 31-November 1 2013.
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An extensive region in Argentina covering an area larger
than Texas received rainfall totals exceeding 1 inch/day
through the early morning of November 1 2013. Within this area,
13 stations in Cordoba and Santa Fe reached amounts between
50 and 150 mm/day. The several ingredients that interacted
for the generation of such event are analyzed, being the most
remarkable high values of precipitable water (>50mm), a low-level
jet from the north, and enhanced upper divergence in the
divergent (left) entrance of a subtropical upper jet.
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3. Gilbert Miller
Country: Cayman Islands
Desk: Tropical
Training: Forecaster
Date: 2013 November
PDF in English
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Nortes event in Mexico.
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A Nortes event is a surge of strong northerly winds along
coastal locations in the western Gulf of Mexico. It is caused
by the combined effects of a robust polar high
over the southwestern Plains of the USA and the funneling
effects of the Sierra Madre Occidental. Strong orographic
uplift as the winds interact with the mountains of southern
and eastern Mexico can lead to excessive rainfall amounts.
This presentation explores an early season event that produced
diurnal rainfall totals between 100 and 200mm/day. It also
elaborates on the forecast from the Tropical Desk perspective.
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2. Sara Olivares
Country: Peru
Desk: South American
Training: Forecaster
Date: 2013 September
PDF in Spanish
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South American Desk Routine and case study of
cold front and shear line on Tropical
South America.
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The South American Desk routine is briefly described.
The study then focuses on a winter cold front that
made it into 07S accompanied by a shear line that
extendsd into the Peru-Colombia border.
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1. Romayne Robinson
Country: Jamaica
Desk: Tropical
Training: Forecaster
Date: 2013 September
PDF in English
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Short review of forecasting methods, tools and
guidelines studied at the Tropical Desk.
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A short review of the methods, tools and guidelines
for quantitative precipitation forecasting at the
Tropical Desk is here reviewed. This includes the
development and use of streamline analysis charts,
interpretation of model guidance, analysis of waves
in the trades, the use of timeseries and
timesections, and the elaboration of forecast
charts.
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