skewt

1 files changed, 96 insertions, 0 deletions

diff --git a/skewt.py b/skewt.py
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+#!/usr/bin/env python3
+
+# https://unidata.github.io/MetPy/latest/examples/plots/Skew-T_Layout.html#sphx-glr-examples-plots-skew-t-layout-py
+
+import matplotlib.gridspec as gridspec
+import matplotlib.pyplot as plt
+
+import csv
+
+import metpy.calc as mpcalc
+from metpy.cbook import get_test_data
+from metpy.plots import add_metpy_logo, Hodograph, SkewT
+from metpy.units import units
+from metpy.calc import parcel_profile
+
+import datetime
+import requests
+
+
+STATION=10548
+DATE=(datetime.date.today() - datetime.timedelta(days = 1)).strftime('%Y-%m-%d')
+TIME='23:00:00'
+# http://weather.uwyo.edu/cgi-bin/bufrraob.py?datetime=2023-07-20%2023:00:00&id=10548&type=TEXT:CSV
+URL=f'http://weather.uwyo.edu/cgi-bin/bufrraob.py?datetime={DATE}%20{TIME}&id={STATION}&type=TEXT:CSV'
+
+print(URL)
+
+result = requests.get(URL)
+RAW_DATA_LINES=result.content.decode('UTF-8').splitlines()
+
+p = []
+T = []
+Td = []
+wind_speed = []
+wind_dir = []
+
+csvreader = csv.reader(RAW_DATA_LINES, dialect='excel')
+next(csvreader) # Skip header
+for row in csvreader:
+    if sum(map(lambda s : len(s.strip()) == 0, row)):
+        # skip any line with empty values
+        continue
+
+    p.append(float(row[3]))
+    T.append(float(row[5]))
+    Td.append(float(row[6]))
+    wind_speed.append(float(row[12]))
+    wind_dir.append(float(row[11]))
+
+
+p = p * units.hPa
+T = T * units.degC
+Td = Td * units.degC
+wind_speed = wind_speed * units.knots
+wind_dir = wind_dir * units.degrees
+u, v = mpcalc.wind_components(wind_speed, wind_dir)
+
+ground_parcel = parcel_profile(p, T[0], Td[0])
+
+# Create a new figure. The dimensions here give a good aspect ratio
+fig = plt.figure(figsize=(9, 9))
+
+# Grid for plots
+gs = gridspec.GridSpec(3, 3)
+skew = SkewT(fig, rotation=45, subplot=gs[:, :])
+
+# Plot the data using normal plotting functions, in this case using
+# log scaling in Y, as dictated by the typical meteorological plot
+skew.plot(p, T, 'r')
+skew.plot(p, Td, 'g')
+skew.plot(p, ground_parcel, 'b')
+
+barb_div = int(len(p)/20)
+skew.plot_barbs(p[::barb_div], u[::barb_div], v[::barb_div])
+
+skew.shade_cape(p,T,ground_parcel)
+skew.shade_cin(p,T,ground_parcel)
+
+skew.ax.set_ylim(1000, 100)
+
+# Add the relevant special lines
+skew.plot_dry_adiabats()
+skew.plot_moist_adiabats()
+skew.plot_mixing_lines()
+
+# Good bounds for aspect ratio
+skew.ax.set_xlim(-30, 40)
+
+# Create a hodograph
+ax = fig.add_subplot(gs[0, -1])
+h = Hodograph(ax, component_range=60.)
+h.add_grid(increment=20)
+h.plot(u[::barb_div], v[::barb_div])
+
+# Show the plot
+plt.show()