Tropical Cyclone Report

Tropical Storm Alma

(EP012008)

29-30 May 2008

Daniel P. Brown

National Hurricane Center

7 July 2008

Alma was the first eastern North Pacific basin tropical storm or
hurricane to make landfall along the Pacific Coast of Central America
since records began in 1949.

a.  Synoptic History

    Unlike most tropical cyclones in the eastern Pacific basin, it
    appears that Alma formed without the assistance of a tropical wave.
    Instead, Alma originated from a nearly stationary trough of low
    pressure that became established over the far eastern portion of the
    basin in late May. Alma's incipient low formed within the broad
    monsoon-like flow early on 27 May, about 225 n mi southwest of the
    coast of Nicaragua. This low may have been initiated by an
    eastward-propagating disturbance as suggested by Hovmöller diagrams
    of satellite imagery. The low pressure area moved eastward, steered
    by the larger cyclonic gyre over the area. The first Dvorak
    satellite intensity estimates were performed on the system by the
    Tropical Analysis and Forecast Branch (TAFB) and the Satellite
    Analysis Branch (SAB) at 0545 UTC 28 May. Shower and thunderstorm
    activity continued to become organized around the low later that
    day, leading to the formation of a tropical depression by 0000 UTC
    29 May, centered about 85 n mi west-northwest of Cabo Blanco, Costa
    Rica. This genesis location is farther east than any eastern North
    Pacific tropical cyclone on record (not including cyclones that
    originated in the Atlantic basin, crossed Central America and
    reformed in the eastern Pacific). The "best track" chart of the
    tropical cyclone's path is given in Fig. 1, with the wind and
    pressure histories shown in Figs. 2 and 3, respectively. The best
    track positions and intensities are listed in Table 1.

    After genesis the depression turned northward and strengthened,
    becoming a tropical storm six hours later. Alma continued to quickly
    intensify, and passive microwave satellite imagery revealed an
    eye-like feature around 1200 UTC (Fig. 4) 29 May. Alma reached an
    estimated peak intensity of 55 kt by 1800 UTC, while centered about
    45 n mi southwest of Managua, Nicaragua. Alma maintained this
    intensity until landfall, which took place about 1945 UTC along the
    Pacific coast of Nicaragua, just southwest of Leon.

    After crossing the coast of Nicaragua, Alma began to weaken, but the
    cyclone maintained tropical storm strength while it moved into
    southern Honduras just after 0000 UTC 30 May. Six hours later, Alma
    weakened to a tropical depression, and by 1800 UTC the low-level
    center dissipated over the mountains of western Honduras. A remnant
    low- to mid-level circulation, however, appears to have moved into
    the extreme western Caribbean and played a role in the development
    of Atlantic basin Tropical Storm Arthur on 31 May.

b.  Meteorological Statistics

    Observations in Alma (Figs. 2 and 3) include satellite-based Dvorak
    technique intensity estimates from TAFB and SAB. Data and imagery
    from NOAA polar-orbiting satellites, the NASA Tropical Rainfall
    Measuring Mission (TRMM), the NASA QuikSCAT, the NASA Aqua, the
    Department of Defense Windsat, and Defense Meteorological Satellite
    Program (DMSP) satellites, among others, were also useful in
    tracking Alma.

    Dvorak satellite intensity estimates provided the basis for
    estimating Alma's intensity during most of its lifetime. Alma's 45
    kt estimated intensity in the best track at 1200 UTC 29 May,
    however, is based on scatterometer surface wind data from the
    QuikSCAT satellite.

    During the hours leading up to Alma's landfall, several consecutive
    passive microwave satellites detected an incipient eye-like feature
    (Fig. 4). Conventional visible satellite imagery during that time
    showed evidence of a transient and ragged banding eye-like feature.
    The estimated peak intensity of 55 kt at 1800 UTC 29 May is based on
    subjective Dvorak intensity estimates of 55 kt from both TAFB and
    SAB. Despite the appearance of the eye-like feature, there is no
    quantitative data to suggest that Alma was stronger than 55 kt.
    Objective Automated Dvorak Technique (ADT) intensity estimates from
    the Cooperative Institute for Meteorological Satellite Studies
    (CIMSS) at the University of Wisconsin were slightly lower than the
    subjective Dvorak estimates during this time. The only report of
    sustained winds of tropical storm force in association with Alma was
    from an observing site in Corinto, Nicaragua. This site is just west
    of where Alma made landfall and it reported peak sustained winds of
    40 kt at 2200 UTC 29 May (Table 2). The lowest minimum pressure
    reported in Nicaragua was 999.8 mb at 2100 UTC 29 May at Chinandega.

Alma and its incipient low produced heavy rainfall over much of Central
America. Reports show that the largest amounts fell in Costa Rica and
Nicaragua (Table 2). The highest storm total (28-29 May) recorded in
Costa Rica was 14.82 in at Quepas. The highest amounts reported in
Nicaragua were 11.72 in at Punto Sandino and 10.52 in at Chinandega.

c.  Casualty and Damage Statistics

    Media reports indicate that Alma was responsible for two direct
    deaths, with nine people currently missing. One of the direct deaths
    occurred in Honduras when a young girl was swept away while trying
    to cross a raging stream. The other death occurred offshore when a
    fishing vessel sank; two other persons onboard remain missing. A
    second small fishing boat with seven people on board also remains
    missing as of this writing.

    Alma is also responsible for seven indirect deaths. Two of the
    indirect deaths occurred in Nicaragua and were the result of
    electrocutions from downed power lines. Weather associated with Alma
    was partially to blame for an aircraft accident in Tegucigalpa,
    Honduras around 1600 UTC 30 May. A Transportes Aéreos del Continente
    Americano (TACA) Airbus A-320 carrying 133 passengers and crew
    skidded off the runway at the Toncontin International Airport. Three
    people on the plane and two others on the ground perished.

    According to a report from the United Nations (UN) Office for the
    Coordination of Humanitarian Affairs (OCHA), the hardest hit areas
    in Costa Rica were the cities of Guanacaste and Punta Arenas. In
    these areas more than a thousand homes were damaged and 150 were
    destroyed. Over 100 roads and bridges in Costa Rica were damaged,
    which left many communities isolated for several days. According to
    some reports, the flooding from Alma in Costa Rica was worse than
    the flooding experienced from Hurricane Cesar (1996) or Mitch
    (1998). Monetary losses in Costa Rica are estimated at \$33 million
    U.S. dollars.

    The OCHA report indicated that about 200 homes were damaged in the
    Nicaraguan provinces of Leon and Chinandega, while in Honduras about
    175 homes suffered damage. No monetary damage totals are available
    from Nicaragua or Honduras.

d.  Forecast and Warning Critique

    The genesis of Alma was well anticipated. The area of disturbed
    weather from which Alma formed was first introduced in the Tropical
    Weather Outlook about 48 h prior to development and the possibility
    of tropical depression formation was explicitly mentioned in the
    outlook beginning about 18 h before genesis. Categorical chances of
    development on the NHC's experimental graphical Tropical Weather
    Outlook initially indicated a low (\<20%) chance of genesis from
    about 36-48 h prior to formation. The chances were increased to
    medium (20-50%) about 36 hours prior to formation, and to high
    (\>50%) about 12 hours prior to genesis.

    The average official track errors for Alma (with number of cases in
    parenthesis) were 24 (5), 55 (3), and 85 (1) n mi for the 12, 24,
    and 36 h forecasts, respectively. Due to the small number of
    forecasts, a meaningful comparison of the official forecast with the
    various track models is not possible. The mean NHC track errors for
    Alma are comparable with the recent 5-year (2003-2007) mean errors.
    All of the NHC forecasts accurately predicted landfall along the
    northwest coast of Nicaragua, though the first couple of forecasts
    predicted a slower forward speed. This resulted in the tropical
    storm making landfall a little earlier than initially predicted.

    Average official intensity errors were 9, 7, and 0 kt for the 12,
    24, and 36 h forecasts, respectively. For comparison, the average
    long-term official intensity errors are 6, 11, and 14 kt,
    respectively. The first two NHC intensity forecasts exhibited a low
    bias as they predicted only modest intensification of Alma.

    Table 3 is a summary of coastal watches and warnings issued in
    association with Alma. Hurricane warnings were issued at 1600 UTC 29
    May by the governments of Honduras and Nicaragua, in conjunction
    with a Special Forecast Advisory issued by NHC that indicated that
    Alma could become a hurricane prior to landfall.

Table 1. Best track for Tropical Storm Alma, 29-30 May 2008.

+----------+---------+---------+---------+--------+-----------------+
| D        | L       | Lo      | P       | Wind   | Stage           |
| ate/Time | atitude | ngitude | ressure | Speed  |                 |
|          |         |         |         |        |                 |
| (UTC)    | \(N\)   | \(W\)   | (mb)    | (kt)   |                 |
+----------+---------+---------+---------+--------+-----------------+
| 29 /     | 10.1    | 86.5    | 1003    | 30     | tropical        |
| 0000     |         |         |         |        | depression      |
+----------+---------+---------+---------+--------+-----------------+
| 29 /     | 10.7    | 86.7    | 1002    | 35     | tropical storm  |
| 0600     |         |         |         |        |                 |
+----------+---------+---------+---------+--------+-----------------+
| 29 /     | 11.3    | 86.8    | 1000    | 45     | \"              |
| 1200     |         |         |         |        |                 |
+----------+---------+---------+---------+--------+-----------------+
| 29 /     | 12.0    | 86.9    | 994     | 55     | \"              |
| 1800     |         |         |         |        |                 |
+----------+---------+---------+---------+--------+-----------------+
| 30 /     | 12.9    | 87.1    | 998     | 45     | \"              |
| 0000     |         |         |         |        |                 |
+----------+---------+---------+---------+--------+-----------------+
| 30 /     | 14.1    | 87.4    | 1004    | 30     | tropical        |
| 0600     |         |         |         |        | depression      |
+----------+---------+---------+---------+--------+-----------------+
| 30 /     | 15.0    | 88.0    | 1006    | 25     | \"              |
| 1200     |         |         |         |        |                 |
+----------+---------+---------+---------+--------+-----------------+
| 30 /     |         |         |         |        | Dissipated      |
| 1800     |         |         |         |        |                 |
+----------+---------+---------+---------+--------+-----------------+
| 29 /     | 12.0    | 86.9    | 994     | 55     | Maximum wind    |
| 1800     |         |         |         |        | and minimum     |
|          |         |         |         |        | pressure        |
+----------+---------+---------+---------+--------+-----------------+
| 29 /     | 12.3    | 87.0    | 994     | 55     | Landfall near   |
| 1945     |         |         |         |        | Leon, Nicaragua |
+----------+---------+---------+---------+--------+-----------------+

Table 2. Selected surface observations for Tropical Storm Alma, 29-30
May 2008.

+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Location        | M   |     | M   |       |     | St  | St  | To  |
|                 | ini |     | axi |       |     | orm | orm | tal |
|                 | mum |     | mum |       |     | su  |     |     |
|                 | Sea |     | S   |       |     | rge | t   | r   |
|                 | Le  |     | urf |       |     |     | ide | ain |
|                 | vel |     | ace |       |     | (   |     |     |
|                 | Pr  |     |     |       |     | ft) | (   | (   |
|                 | ess |     | W   |       |     | ^c^ | ft) | in) |
|                 | ure |     | ind |       |     |     | ^d^ |     |
|                 |     |     | Sp  |       |     |     |     |     |
|                 |     |     | eed |       |     |     |     |     |
+=================+=====+=====+=====+=======+=====+=====+=====+=====+
|                 | Da  | Pre | Da  | Sust  | G   |     |     |     |
|                 | te/ | ss. | te/ | ained | ust |     |     |     |
|                 |     |     |     |       |     |     |     |     |
|                 | t   | (   | t   | (k    | (   |     |     |     |
|                 | ime | mb) | ime | t)^b^ | kt) |     |     |     |
|                 |     |     |     |       |     |     |     |     |
|                 | (U  |     | (U  |       |     |     |     |     |
|                 | TC) |     | TC) |       |     |     |     |     |
|                 |     |     | ^a^ |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| **Nicaragua     |     |     |     |       |     |     |     |     |
| ^e^**           |     |     |     |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Chinandega      | 2   | 99  | 3   | 28    |     |     |     | 10  |
|                 | 9/2 | 9.8 | 0/0 |       |     |     |     | .51 |
|                 | 100 |     | 000 |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Corinto         |     |     | 2   | 40    |     |     |     | 9   |
|                 |     |     | 9/2 |       |     |     |     | .42 |
|                 |     |     | 200 |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Leon            |     |     | 2   | 26    |     |     |     | 4   |
|                 |     |     | 9/1 |       |     |     |     | .65 |
|                 |     |     | 900 |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Managua         |     |     |     |       |     |     |     | 2   |
|                 |     |     |     |       |     |     |     | .72 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Masatepe        |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .74 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Nandaime        |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .20 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Monterosa       |     |     |     |       |     |     |     | 9   |
|                 |     |     |     |       |     |     |     | .60 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Ineter Central  |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .25 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Punto Morazan   |     |     |     |       |     |     |     | 6   |
|                 |     |     |     |       |     |     |     | .46 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| S.J. Achuapa    |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .84 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Gallo Nombre de |     |     |     |       |     |     |     | 6   |
| Jesus           |     |     |     |       |     |     |     | .67 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Villa Nueva     |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .59 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| El Sauce        |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .95 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Telica          |     |     |     |       |     |     |     | 6   |
|                 |     |     |     |       |     |     |     | .23 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Somotillo       |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .82 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Pueblo Nuevo    |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .02 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Matagalpa       |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .69 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Los Quesos      |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .87 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Jinotega        |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .63 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| San Isidro      |     |     |     |       |     |     |     | 6   |
|                 |     |     |     |       |     |     |     | .61 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Punto Sandino   |     |     |     |       |     |     |     | 11  |
|                 |     |     |     |       |     |     |     | .72 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Granada         |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .17 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Masaya          |     |     |     |       |     |     |     | 6   |
|                 |     |     |     |       |     |     |     | .07 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
|                 |     |     |     |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| **Honduras      |     |     |     |       |     |     |     |     |
| ^e^**           |     |     |     |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Puerto Lempira  |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .45 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Choluteca       |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .46 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
|                 |     |     |     |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
|                 |     |     |     |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| **Costa Rica    |     |     |     |       |     |     |     |     |
| ^f^**           |     |     |     |       |     |     |     |     |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Liberia         |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .33 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Hacienda Mojica |     |     |     |       |     |     |     | 9   |
|                 |     |     |     |       |     |     |     | .89 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| La Ceiba        |     |     |     |       |     |     |     | 13  |
|                 |     |     |     |       |     |     |     | .93 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Santa Rosa      |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .00 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Nicoya          |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .57 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Jaco            |     |     |     |       |     |     |     | 10  |
|                 |     |     |     |       |     |     |     | .06 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Damas           |     |     |     |       |     |     |     | 11  |
|                 |     |     |     |       |     |     |     | .69 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| P. Seco         |     |     |     |       |     |     |     | 13  |
|                 |     |     |     |       |     |     |     | .27 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Quepos          |     |     |     |       |     |     |     | 14  |
|                 |     |     |     |       |     |     |     | .82 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Golfito         |     |     |     |       |     |     |     | 6   |
|                 |     |     |     |       |     |     |     | .80 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Coto 47         |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .40 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Rio Claro       |     |     |     |       |     |     |     | 3   |
|                 |     |     |     |       |     |     |     | .13 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| San Jose        |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .55 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Alajuela        |     |     |     |       |     |     |     | 7   |
|                 |     |     |     |       |     |     |     | .99 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Pavas           |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .73 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Cigefi          |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .09 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Atenas          |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .82 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Upala           |     |     |     |       |     |     |     | 5   |
|                 |     |     |     |       |     |     |     | .19 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+
| Catie           |     |     |     |       |     |     |     | 4   |
|                 |     |     |     |       |     |     |     | .40 |
+-----------------+-----+-----+-----+-------+-----+-----+-----+-----+

^a^ Date/time is for sustained wind when both sustained and gust are
listed.

^b^ Except as noted, sustained wind averaging periods for C-MAN and
land-based ASOS reports are 2 min; buoy averaging periods are 8 min.

^c^ Storm surge is water height above normal astronomical tide level.

^d^ Storm tide is water height above National Geodetic Vertical Datum
(1929 mean sea level).

^e^ Rainfall total between 29-30 May.

^f^ Rainfall total between 28-29 May.

Table 3. Watch and warning summary for Tropical Storm Alma, 29-30 May
2008.

  ----------- ------------------------------ ------------------------------
  Date/Time   Action                         Location
  (UTC)                                      

  29/ 0300    Tropical Storm Warning issued  Pacific coast of Costa Rica

  29/ 0900    Tropical Storm Warning issued  Pacific coast of El Salvador

  29/ 1200    Tropical Storm Warning issued  Pacific coast of Nicaragua and
                                             the Pacific coast of Honduras

  29/ 1600    Tropical Storm Warning         Pacific coast of Nicaragua and
              replaced with a Hurricane      the Pacific coast of Honduras
              Warning                        

  29/ 1600    Hurricane Watch issued         Pacific coast of El Salvador

  29/ 2100    Hurricane Warning replaced     Pacific coast of Nicaragua and
              with a Tropical Storm Warning  the Pacific coast of Honduras

  29/ 2100    Hurricane Watch discontinued   Pacific coast of El Salvador

  29/ 2100    Tropical Storm Warning         Pacific coast of Costa Rica
              discontinued                   south of Jaco

  30/ 0300    Tropical Storm Warning         Remainder of the Pacific coast
              discontinued                   of Costa Rica

  30/ 0900    Tropical Storm Warning         Pacific coast of Honduras and
              discontinued                   the Pacific coast of El
                                             Salvador

  30/ 1200    Tropical Storm Warning         Pacific coast of Nicaragua
              discontinued                   
  ----------- ------------------------------ ------------------------------

![](media/image1.jpeg){width="7.996527777777778in"
height="6.179166666666666in"}

Figure 1. Best track positions for Tropical Storm Alma, 29-30 May 2008.

![](media/image2.wmf){width="8.51875in" height="5.839583333333334in"}

Figure 2. Selected wind observation, Dvorak analysis estimates, and best
track maximum sustained surface wind speed curve for Tropical Storm
Alma, 29-30 May 2008. Thin solid vertical line denotes landfall.

![](media/image3.wmf){width="8.502083333333333in"
height="5.839583333333334in"}

Figure 3. Dvorak pressure analyses and best track minimum central
pressure curve for Tropical Storm Alma, 29-30 May 2008. Thin solid
vertical line denotes landfall.

a\) 0709 UTC 29 May b) 1137 UTC 29 May c) 1342 UTC 29 May

![](media/image4.jpeg){width="2.5in"
height="2.5in"}![](media/image5.jpeg){width="2.5in"
height="2.5in"}![](media/image6.jpeg){width="2.5in" height="2.5in"}

d\) 1414 UTC 29 May e) 1937 UTC 29 May

![](media/image7.jpeg){width="2.5in"
height="2.5in"}![](media/image8.jpeg){width="2.5in" height="2.5in"}

Figure 4. Series of composite 85-91 GHz passive microwave images of
Tropical Storm Alma on 29 May 2008. The images show the evolution of an
eye-like feature and the subsequent landfall along the Pacific coast of
Nicaragua. Images courtesy of the Navy Research Laboratory (NRL).