FRNTDISP

Displays fronts from NCEP frontal positions products.


Format

FRNTDISP map time [keywords]


Parameters

map

map for the fronts; use any predefined map in the MAP command, e.g., MID, USA, NA (default=do not draw map; use navigation of frame specified in NAV keyword)

time

frontal analysis time or model run time; specify as an hour, LATEST or FRAME (default=LATEST), where:
hour = 0, 3, 6, etc.
LATEST = uses the latest analysis within previous 6 hours
FRAME = uses the nearest analysis within 3 hours of the day and time of the image displayed in the frame


Search Keywords

DAY=

analysis day or day of model run (default=current)

FHOur=

forecast hour for forecast fronts; valid entries are 0, 12, 24, 36, or 48 (default=0 - analysis); not valid with FRAME time

FILE=

file to read from if not using weather text dataset; the file must contain only frontal positions products
(default=none - use weather text files)

GROup=

ADDE group to search; the group name must be mapped with the DATALOC command to a server with weather text data (default=RTWXTEXT for weather text; FRONTS for reading from files)


Navigation Keywords

NAV=

frame to use for navigation; specify a frame number or C for the current frame (default=C); no map is drawn; you cannot use this keyword unless the default is used for the map parameter


Display Keywords

BARbsiz=

cold warm

height of cold and warm barbs (default=plot size dependent)

BASe=

length of barb base on front (default=plot size dependent)

COLor=

hi low cold warm ocld stnry trof
graphics color level for each component (default=6 5 hi low 1 hi 3), where:

 

 

hi

High labels and pressure values

 

 

low

Low labels and pressure values

 

 

cold

cold front lines and barbs

 

 

warm

warm front lines and barbs

 

 

ocld

occluded front lines

 

 

stnry

stationary front lines

 

 

trof

dashed trough lines

GRA=

graphics frame number to display output (default=current)

LABel=

'text' color line ele size
text, color, location and size for label, where:

 

 

`text'

label's text; 72 characters maximum; specify an X without quotes for default text (default=computed)

 

 

color

graphics color level of label (default=3)

 

 

line

beginning TV line to write label (default=top of frame)

 

 

ele

beginning TV element to write label (default=left side of the frame minus the length of the label)

 

 

size

size of label text (default=plot dependent)

LSIZE=

hilo pres

height of High and Low labels, and pressure values (default=plot size dependent)

LWIDth=

front hilo pres

line width of front lines, High and Low labels, and pressure values (default=2 2 1)

ORIent=

cold warm ocld stnry
side of the cold, warm, occluded, and stationary front lines that the barbs are drawn, as seen moving out from the Low; specify L for the left side or R for the right side (default=L L L L)

OUTput=

PLOT

plot the frontal positions (default)

 

RAW

list the original text product

 

TAB

list the decoded front point and High/Low positions in a tabular format

SPAce=

distance between barbs along fronts (default=plot size dependent)


Remarks

FRNTDISP draws fronts using the NCEP frontal positions products issued under WMO headers ASUS1 and FSUS2. It accesses these products through the ADDE server mapped to the group name specified in the GROUP keyword.

The current frontal time is defined to be that of the most recent front product received if it falls within six hours of the current clock time.

The direction that the cold and warm barbs face is defined by the front product. If the product does not follow standard conventions, the barbs may face the incorrect way. You change the direction that they face with the ORIENT keyword.


Examples

FRNTDISP

This entry draws the fronts in the most recent NCEP frontal positions analysis product (WMO header ASUS1) on the current frame. No map is drawn; the current frame's navigation is used.

FRNTDISP USA

This entry draws the fronts in the most recent NCEP frontal positions analysis product (WMO header ASUS1) on a map of the United States.

FRNTDISP X FRAME NAV=8 GRA=8

This entry draws, on graphics frame 8, the fronts in the NCEP frontal positions analysis product (WMO header ASUS1) that is nearest in date and time to the image displayed in frame 8.

FRNTDISP USA 0 FHOUR=24

This entry draws the 24-hour forecast fronts in today's 00 UTC NCEP frontal positions forecast product (WMO header FSUS2) on a map of the United States.

FRNTDISP OUT=RAW

This entry lists the most recent NCEP frontal positions analysis product (WMO header ASUS1) on the text window. No fronts are drawn on the graphics frame. If OUT=TAB is specified instead of OUT=RAW, the data is listed in a decoded tabular format that labels the latitude, longitude and pressure of each High and Low, and the latitude and longitude for each point of the troughs and cold, warm, stationary and occluded fronts.