NCL Study Notes (weather analysis chart)

Wind and wind speed vector map

Let's look at a sample picture of wind speed:

This is basically the same as the previous method of drawing the temperature distribution, and the different places are

  Wres@vcrefmagnitudef          = 20.                ; Make vectors larger
  WRES@VCREFLENGTHF             = 0.030             ; Ref VEC length
  wres@vcglyphstyle             = " Windbarb "        ; Select wind Barbs
  WRES@VCMINDISTANCEF           = 0.025              ; Thin out Windbarbs
  Wres@vcwindbarbcolor      = 3
and the last called drawing function

Wplot = Gsn_csm_vector_map (wks,ddata1,vdata1,wres); Create plot

Ddata1 is the wind direction after interpolation, Vdata1 is the wind speed after interpolation

Since the wplot to stack with the previous map, use the Overlayhas function, and finally display the superimposed map

Overlay (Map,wplot)
Draw (map)
Weather analysis Chart of terrestrial meteorological elements

Instead of the real data, the image is drawn as a sample.

1. The element Analysis icon

A 50char string is required to display the icon on the left side of the diagram, with the following data format:

Example

Imdat = "11721700181008020050300004983052026604007289086925"

A string (or array) of characters encoded as per the WMO/NOAA (World Meteorological Organization/United States National Oceanic and Atmospheric Administration) guidelines.
If an array, it must have the same shape as the x and Y arrays.
In more detail (where the characters are numbered from left to right, starting at character number 0):

Character 0 = ir-the precipitation Data indicator (hail index)
Character 1 = Ix-weather data and station type indicator (weather data and site type indices)
Character 2 = H-height above ground of base of lowest cloud
Characters 3-4 = vv-visibility in miles and fractions (visibility)
Character 5 = n-total amount of cloud cover (total cloud cover)
Characters 6-7 = Dd-direction from which winds are blowing (wind direction)
Characters 8-9 = Ff-wind speed in knots (wind speed)

If character = "1", then

character = Sn-sign of temperature
Characters 12-14 = ttt-current air temperature

If character = "2", then

character = Sn-sign of temperature
Characters 17-19 = Td-dew point

If character = "3", then

Characters 21-24 = po-station pressure (not plotted)

If character = "4", then

Characters 26-29 = Pppp-pressure reduced to sea level

If character = "5", then

character = A-characteristic of barograph
Characters 32-34 = ppp-pressure change, last 3 hrs.

If character = "6", then

Characters 36-38 = rrr-precipitation
Character = Tr-time duration of precipitation

If character = "7", then

Characters 41-42 = ww-present Weather
character = w1-most significant past weather
character = w2-2nd most sig. Past Weather

If character = "8", then

character = Nh-fraction of Sky cover
character = Cl-cloud type, low clouds
character = Cm-cloud type, medium clouds
character = Ch-cloud type, high clouds
The data can be converted to 50char according to actual data and transmitted to

WMSTNM (Wks,lat_imdat,lon_imdat,imdat) for drawing

2. Heating and Cooling Peak

WMSETP ("Fro", "warm"); Specify stationary front. ; Cold or warm or stationary (interal)
WMSETP ("CFC", 3); Use the blue for the triangles.
WMSETP ("WFC", 2); Use red for the bumps.
WMSETP ("Swi", 0.02); Increase the size of the bumps and triangles.
WMSETP ("NMS", 2); Set the number of peaks
WMSETP ("Sig", 0.005)
WMSETP ("SLF", 0); 0 Using SL1 and SL2, 1 uses SL1, 2 uses SL2, 3 is not used, the default value
WMSETP ("SL1", 90) ; The angle between the starting direction and the X axis
WMSETP ("SL2", 0) ; The angle between the end direction and the X axis
Xlat = (/25., 30./); Latitudes.
Xlon = (/113., 116./); longitudes.
Wmdrft (wks, Xlat, Xlon)

3. Draw High Pressure Center

Take the high pressure as an example, with the red "D" represented.

Tres = True; Text Mods Desired
TRES@TXFONTHEIGHTF = 0.015; Make smaller
Tres@txfontcolor = 2; Red font

Gsn_text (Wks,map, "D", 123.,51.,tres)

Weather analysis Chart of high altitude meteorological elements

   is the superposition of isotherm and isobars, using the function map = Gsn_csm_contour_map_overlay (Wks,pdata,vdata,res,res2), and others with terrestrial meteorological elements